Strontium is a soft, silver-gray metal with symbol Sr and atomic number 38 that exists as four stable isotopes in nature, most dominantly strontium-88 which comprises 83% of natural strontium. It is found ubiquitously in minerals like celestite and strontianite, making up about 0.025% of the Earth's crust. While strontium has 16 radioactive isotopes, only strontium-90 has a sufficiently long half-life of 29 years to be of concern to human health.
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More Related Content
Osmium Research Paper
1. Osmium Research Paper
How can one human mind organize and memorize over 100 elements? In 1869, Dmitri Mendeleev, a
Russian chemist and inventor, was credited with creating and publishing the Periodic table. The
Periodic table is an arrangement of the chemical elements discovered on earth. These elements are
organized by their atomic number and similarities between chemical properties. The Periodic table
holds 118 elements which can be broken down into smaller classifications, groups (vertical), periods
(horizontal) and blocks (adjacent). In this paper, we will zoom in one unbelievable element
Osmium, which is usually lost in the mix.
Osmium was discovered in 1803 by Smithson Tennant. This element was found when Tennant used
platinum to dilute aqua regia. He noticed ... Show more content on Helpwriting.net ...
For example, osmium can irritate the respiratory system, the skin, and the eyes. Osmium is rarely
used in its pure form, meaning that it can be highly toxic. Effects of inhaling this element include,
burning sensation, coughing, severe headaches, wheezing, sudden shortness of breath, and visual
disturbances. As a result of contact with the skin, you are at risk of redness, skin burns, skin
discoloration and blisters. Unfortunately, exposure to high concentrations may result in damage to
kidneys or even death. Though this chemical is able to do harm, it can be and has been used in a
beneficial way. For example, Osmium has also played a key role in various aspects of the
development of lightbulb technology.Alloys of osmium and platinum are used to make specialized
laboratory equipment. Alloys can be made by melting or mixing two or more metals. Lastly, it can
be used as a catalyst, a substance used to speed up or slow down a chemical reaction.
In summarization,osmium ,Os, is a chemical element based on the periodic table. This element was
discovered in the mixture of a mixture of nitric and hydrochloric acids. It has a atomic number of 76
and an atomic mass of 190.23. This is the most rarest of 118 chemical elements. Though this
element is overlooked, this element has great
... Get more on HelpWriting.net ...
3. John Cusack: The Element Of Neon
John Cusack Sir William Ramsay and Morris M. Travers discovered the element neon in 1898. Sir
William Ramsay and Morris M. Travers took aargon, froze it in a glass bubble, and surrounded it
with liquefied air. Then Ramsay and Travers took away the liquid and ran electricity through the
vapor, which turned into neon! Neon is a noble gas found at group 18 and period 2. Neon has an
element symbol of Ne, has a atomic number of 10, and a atomic mass of 20.179. Neon or Ne is
located at group 18 so therefore neon has 8 valence electrons. Neon is a gas at room temperature,
has a boiling point of –246.1 oC, and a melting point at –248.6 oC. Neon is a non–toxic, tasteless,
smell less, and colorless. Neon though is only colorless if no electrical current is running through it.
If neon has an electrical current going through it neon becomes a bright red–orange color. Neon is
chemically inactive so neon can't react with any other element or compound even under extreme
pressure. Neon is the 4th most abundant element in the universe, but only .0018% of neon is found
in the Earth's atmosphere. Neon is found in Earth's atmosphere. Neon is a renewable resource. Neon
just by itself isn't dangerous, but if you have liquid ... Show more content on Helpwriting.net ...
If you add substances to neon you change the red–orange color to hundreds. Neon is also used more
than just for advertising such as lasers, TV tubes, and cryogenics. Since neon is chemically inactive
neon doesn't have any chemical bonds with other elements. There are three common isotopes of
neon 20Ne, 21Ne, and 22Ne. 20Ne and 22Ne are used for helium–neon laser applications. 21Ne is
used for surface exposure dating. The name neon comes from the Greek word neos, which means
new. Neon gas is expensive because it has to be removed from the air. Neon's crystal structure is
cubic. Neon is the second lightest noble gas, lighter than air! Neon forms in stars with a mass of 8 or
more Earth
... Get more on HelpWriting.net ...
5. Chemical And Periodic Properties: Charlie Ponyik And Dr....
"Chemical and Periodic Properties" Martin Lozano, Charlie Widdicombe Experiment 2 September
5, 2014 Charlie Ponyik and Dr. Renee Falconer Introduction Even before he knew anything about
the atom or its behavior, a Russian scientist by the name of Dmitry Mandeleev was able to organize
known elements of the time by their common properties. He noticed that the properties would
appear periodically and began organizing the elements in columns that shared those similar
properties. Thus, the periodic table was born.2 In this lab session, the chemical and periodic
properties of several substances were observed to determine trends and differences among them.
These properties include, but are not limited to, acidity and basicity, the production of gases, ...
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It is important to note that common household products are generally basic or slightly acidic, and ae
useful for cleaning due to their ability to react with substances that need to be cleaned.1 An acid is
simply a molecular compound that is able to donate a positive Hydrogen ion when dissolved in
water. Conversely, a base is a molecular compound that is able to give off negatively charged
hydroxide ions when dissolved in water.3 Because of this "donation" of ions, chemical changes may
occur. When ionic compounds (compounds consisting of a positive cation and a negative anion
stuck together by the attraction of the other's charge) are dissolved in water, electrolytes are created.
An electrolyte is a substance that conducts electricity when dissolved in water, while a non–
electrolyte is one that cannot.3 In general, those compounds whose ions dissociate in greater amount
and are in greater concentration are more conductive, or have more ability to transmit heat and
electricity. We can demonstrate this dissociation of sodium chloride dissolved in water with the
following chemical
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7. Noble Gas Neon
Mitchell Adamson
Mr. Shipman
Hour 1
January 22, 2016
Tour of the Periodic Table
Can you believe that in 1869 Russian Chemist Dimitri Mendeleev arranged the chemical elements
by atomic mass and started the development of the periodic table. After this Henry Gwyn Moseley
was an English Physicist and Developed Mosley's which sorted the chemical elements of the
periodic table in a logical order based on physics. Before all the naturally occurring elements were
discovered the periodic table was used to predict chemical and physical properties of elements in the
gaps of the table. The periodic table can now be used to predict properties of elements yet to be
discovered. It can also be used to predict types of chemical reactions. The Periodic ... Show more
content on Helpwriting.net ...
The Transition metals are the 38 elements between groups 3 and 12. Along with all metals, these
transition elements are ductile, malleable, and conduct electricity and heat. Their valence electrons
are used to combine with other elements that are present in one shell. The element we are going to
look at from this group is Beryllium. This element has the symbol of Be and has the atomic number
of 4. It is created through stellar nucleosynthesis and is a rare element. It is a gray–metallic color
and is in period 2 of the periodic table. This element is very toxic and has one of the highest melting
point for one of the lightest metals. This element is very harmful for the human body, but is good in
nature. These are the Transition metals and the element
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9. Chemistry Synthesis Essay
The activity was separated into 4 parts concerning 5 different groups of elements. In the first part,
we had identified the physical state, the color, and the solubility in water of the Carbonates of I–A
and II–A Elements. The elements Na2 Co3, Li2 CO3, Mg CO3, Ca CO3 had a powdery appearance
while Ba CO3 had a ball shape appearance and K2 CO3 had a wet, granule appearance. All of the
elements stated have a white color. The elements Na2 Co3, Li2 CO3, K2 CO3 were soluble to water
while Mg CO3 Ca CO3 Ba CO3 were not. For the second part, we had identified the physical state
and the color of some of the Group IV–A Elements. Carbon had a powdery appearance and it is
black in color. Silicon had a ball–shaped appearance and it is countable and it is pinkish–white in
color. ... Show more content on Helpwriting.net ...
Lead has a ball shaped appearance and it is gray in color. For the third part, we had a group of
elements, Group II–A Metal Oxides, undergo the litmus paper test and identified its chemical
equation. MgO,CaO ,BaO all had the same results on the test, with all having Red → Blue, Blue →
Blue results resulting having almost the same chemical equations with MgO having MgO + H2O →
Mg(OH)2 , CaO having CaO + H2O → Ca(OH)2 and BaO having Ba + H2O → Ba(OH)2. As for
the last part, we had a different group of elements, Group V–A Nonmetal Oxides, undergo the litmus
paper test and identified its chemical equation. The elements P2O5, Sb2O3 did not undergo any
change so there is no need for a chemical equation while Nitric acid + Copper changed color from
blue to red so it's chemical equation is 4HNO3 + Cu → Cu(NO3)2 + 2H2O +
... Get more on HelpWriting.net ...
11. The Development Of The Periodic Table
Chemistry Research assignment
OUTLINE the history of the development of the Periodic Table including its origins, the original
data used to construct it and the predictions made after its construction. (Include references to the
contributions made by Antoine Lavoisier, Johann Dobereiner, John Newlands, Dmitri Mendeleev,
Lothar Meyer, William Ramsay, Henry Moseley, J.J. Thomson and Niels Bohr.
In 1803 a man by the name of John Dalton Proposed that matter was comprised of atoms that were
very simple and solid with no structure. He also put forward that each element was different from
each other with different atomic weights. J.J. Thomson first discovered the electron in 1897 which
lead to him developing a new model of the atom in 1904 – 1909, this new model is often referred to
as the plum pudding model due to Thomson visualizing the atom as a positive sphere in which
negative electrons embedded into it. Thomson envisaged the electrons to have some sort of structure
or pattern to them rather than just loose as the name, plum pudding implies. Earnest Rutherford
Developed an atomic model in 1911 called the planetary model. This model has positive protons in
the nucleus with negative electrons orbiting it like the sun. He developed this model due to him
discovering the nucleus. Later in 1913 Niels Bohr Realised that the electrons that orbit the nucleus
must occupy stable, non–radiating orbits. This led to him developing the Bohr Model which was
electrons occupying stable shells
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13. Roles Involved In Fireworks
The Role of Black powder in Fireworks
Fireworks are a device containing gunpowder and other combustible chemicals. Fireworks cause
spectacular effects and explosions when ignited. They are most commonly used for display on in
celebrations (William Collins Sons & Co, N/D). Fireworks are spectacular as they produce amazing
bursts of colour that form a variety of shapes. 2 main reactions occur in fireworks to produce their
magnificent display. Stars are used to create the colours in fireworks after their explosion (Dingley,
2015). Black powder is used for the propulsion of the aerial shell into the air. The Black powder also
causes the bursting of the aerial shell causing the stars to be released (Antonis, 2010).
Black powder is a substance ... Show more content on Helpwriting.net ...
Meaning the element gains electrons during the reaction. This occurs with the nitrogen in the
potassium nitrate (reactant) and the Nitrogen (product). The oxidation number of nitrogen in the
potassium nitrate is positive 5 and the oxidation number of the nitrogen is 0. Therefore during the
reaction the nitrogen has gained 5 electrons. Therefore this classifies as a reduction reaction.
The potassium nitrate in this reaction is a spectator ion as it does not react or change form. This is
due to the potassium always being in a compound meaning it never changes charge.
Fireworks utilize an array of chemical reactions and different chemical compounds to produce a
spectacular display of light and sound. These chemical reactions include redox reactions,
combination reactions and displacement reactions. All of these chemical reactions equally take part
in the production of the light and sound of the
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15. Chemistry : The Chemical And Physical Properties Of Chemistry
By definition, chemistry is the scientific branch concerned with atoms, molecules, chemical
elements and how they form compounds and undergo reactions.
This science gave humanity the chance to understand not only the chemical and physical properties
of chemical elements and compounds, it unlocked endless opportunities for humans to prepare, find,
and use these elements in every field and aspect in their daily life. This includes engineering,
medicine, nutrition, scientific research, experiments and industries.
A chemical element is a species of atoms having the same number of protons in their atomic nuclei
(that is, the same atomic number or Z). 118 elements are found, of which the first 94 occur naturally
on Earth with the remaining 24 being synthetic elements.
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical
element.
Every solid, liquid, and gas is made up of neutral or ionized (gaining or losing electrons) atoms.
Chemical elements constitute all the ordinary matter in the universe excluding dark matter in space
which is yet to be discovered and studied.
The most common elements on earth are hydrogen, and helium that mostly formed after the big
bang.
All chemical elements known to mankind are present in the "Periodic Table" that arranges them and
summarizes their chemical properties.
One of the mostly used chemical elements in life is Copper "Cu"
The word copper derives from the Latin "cuprum," which translates into
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17. The Chemical Element Calcium
What is Calcium? The chemical element Calcium (Ca) is a malleable, ductile, soft metal. It's located
in period four and group two of the periodic table. Calcium atoms have 20 electrons and 20 protons,
there are two valence electrons in the outer shells. Its mass number is approximately 40.08. Calcium
has four stable isotopes including 40Ca, 42Ca, 43Ca, and 44Ca; 97% of naturally occurring calcium
is in the isotope 40Ca. Isotopes are atoms that have the same number of protons and electrons, but a
different number of neutrons. In nature, calcium does not appear as a metal itself instead it appears
in the form of rocks and minerals such as limestone, dolomite, and gypsum. Calcium can be found
in countries such as Russia, China, USA, and France.
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19. How Strontium Is A Chemical Element With Symbol Sr And...
Strontium is a chemical element with symbol Sr and atomic number (protons in nucleus) 38 and
atomic weight 88.1 It is a soft, silver–gray metal, and has physical and chemical properties like to
Calcium and Barium. It is available as four stable isotopes ubiquitously (Isotopes are differ in forms
of an by number of protons in nucleus but possess a variable number of neutrons.) Strontium–88 is
the most dominant among other forms, comprising 83% of natural strontium, where in additional
three stable isotopes and their relative abundance are strontium–84 (0.6%), strontium–86 (9.9%),
and strontium–87 (7.0%). Strontium is available ubiquitous vitally as as celestite (SrSO4) and
strontianite (SrCO3), and it comprises about 0.025% of the earth's crust. There are 16 major
radioactive isotopes of strontium, but only strontium–90 has a half–life sufficiently long (29 years).
In comparison with half–lives of remaining strontium radionuclides are fewer than 65 days.
Strontium–90 decays to yttrium–90 by decaying a beta particle, and yttrium–90 decays by decaying
a energetic beta particle with a half–life of 64 hours to zirconium–90. The key health concerns for
strontium–90 are associated to the energetic beta particle from yttrium–90.2
Strontium–90 is a pure β emitter, produced in nuclear fission of (235U and 239Pu fission reaction).
When an atom of uranium–235 (or other fissile nuclide) fissions, usually splits asymmetric into two
large fragments – fission products possessing mass
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21. Why The Chemical Elements Are Given A Unique Atomic Number
All the chemical elements are given a unique atomic number; copper is the 29 atomic numbers.
Atoms are made of three kinds of smaller particles, called protons, neutrons and electrons the atomic
number is the number of protons in the atom. Each element is first identified at room temperature
and pressure as being solid, liquid or gas therefore copper is a solid. Elements, like copper, have
other properties and characteristics physical properties can be observed and measured whereas
chemical properties is how an element reacts with other substances. Copper is capable of being bent
and shaped also it can be easily pulled or stretched into thin wire. Copper has a shine to it; it is an
excellent transmission of heat and electricity since it is a good conductor. The maximum density of
Copper is 8.96 g/cm3.
Copper is a ductile metal with high thermal and electrical conductivity. Ductility is a measure of
how much pressure a metal can take before breaking apart. A metal with high malleability will be
able to be drawn into long, thin wires without rupturing whereas a metal with low malleability will
be brittle, although it may be strong, once it deforms enough, it will rupture. Most metals like
Copper, gold, silver and aluminum are malleable because atoms can roll over each other and retain
the structure of crystal, a function of metallic bonding. Copper is a pinkish color when it is new, but
soon turns a reddish orange color after it is exposed to air, it is soft and bendy.
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23. Chlorine Research Paper
Chlorine
Chlorine has 17 protons, 18 neutrons, and 17 electrons. It's atomic number is 17 and the atomic
mass is 35.45. Its symbol on the periodic table is Cl.
Question #1
It is surprising how many ways humans use chlorine. One way humans use chlorine is to kill
bacteria and germs in pools. It cleanses the pool so when people go swimming, they will not get
sick. Chlorine is also used to make paper. Scientists use it to drain all the color to make it white.
Chlorine is also used in the water purification process. It kills bacteria in the water system before it
enters a house. Chlorine is also found in many common things like, bleach. Bleach makes clothes
white to take out at the stains. The salt many people have on their table is composed up of one
sodium and one chlorine atom. There are not natural sources of chlorine in its pure element (gas)
form. But it is mostly found in the earth's crust along with sodium, potassium, and manganese
chlorides. The impacts chlorine has on the environment depends on how long it is the environment
and how much of the substance is present. Sometimes chlorine combines to form harmful chemicals
that gets into water ... Show more content on Helpwriting.net ...
Some physical properties are its greenish–yellow color (only is gas form). Its disagreeable,
suffocating smell, solubility in water, and a boiling point of –34.05°C. It also has a melting point of
–101°C, a density of 3.214 g/l, and a gravity of –33.6°C. These properties are physical and not
chemical because when observed, they do not change the chemical makeup of that matter (in this
case chlorine). The properties are also easily observed with the 5 senses. But how does chlorine get
its physical properties? Chlorine gets its properties from the number of protons in the nucleus.
Different elements have different numbers of protons, which means they have different
chemical/physical
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25. Chlorine Experiment
Introduction:
The element I have chosen to research for my assignment is Chlorine. It is a very important element
as Chlorine is in a lot of things that most people use in their everyday lives.
Chlorine is an element of the periodic table. It's chemical symbol is Cl, it has the atomic number of
17 and an approximate atomic mass of 35.5. It was discovered by a man named Carl Wilhelm Sceele
who mistakenly thought it was a gas that contained oxygen and discovered chlorine and noticed its
other properties and uses.
Physical and Chemical Properties:
Chlorine, being an element owns a variety of physical and chemical properties such as that it is a gas
which means it is a non–metal making it impossible to be lustrous, hard, conductors ... Show more
content on Helpwriting.net ...
The thing that is different with chlorine when mixing with hydrogen is that it doesn't burn or
explode when in contact with it (eg. Oxygen). During the process of combining, a solution called
hydrogen chlorine is produced.
Where is it found / How is it made?
Where is it found:
Chlorine is located in abundance in the Earth's crust and exists closer that thought. Chlorine can be
found as the compound, sodium chlorine, which is found in the Earth's oceans. Chlorine can also be
made.
How is it made:
Chlorine first exists as a compound called sodium chlorine which is located in Earth's oceans. To
actually make chlorine, first it must be extracted from the ocean and taken to a lab or place where it
must be manufactured by using the process of electrolysis to get chlorine. During the production
process, two co–products are produced: hydrogen gas and caustic soda.
Why is it important and what are its uses
Chlorine has many uses and importance as it is a very commonly overlooked thing that changes
people's lives. First of all, chlorine can be used as a very effective antiseptic which can stop wounds
and sores from being infected or stopping something nasty spreading
28. The History of Chemistry Essay
History of Chemistry
Chemistry has been around for a various amount of years. The beginning of chemistry was first
acknowledged in 10,000 BC. The ancient civilizations used technologies that came to become the
makeup of the many branches of chemistry. These early civilizations would extract metal from ores,
make pottery and glazes, beer and wine fermentation, extraction of chemicals from plants for
medicine, making fat into soap, making glass, and many chemistry related tasks were done.
Alchemists set the stage for modern chemistry by performing experiments and recording the results.
Robert Boyle wrote The Sceptical Chymist in 1661, and in this book it he talks about the difference
between chemistry and alchemy. Although was not the ... Show more content on Helpwriting.net ...
Henry Cavendish had isolated hydrogen in 1766. He soon called "inflammable air." In 1773, Carl
Wilhelm Scheele discovered oxygen. He came to call this "fire air." Scheele had not published his
achievement soon enough, and Joseph Priestley did instead. Priestley revered to oxygen as
"dephlogisticated air." He had also invented soda water. In 1789 Antoine Lavoisier, father of modern
chemistry, established the law of conservation of mass, Lavoisier's law. He had made a system
which named chemical compounds. This was put into his book called Methods of Chemical
Nomenclature in 1787. This chemical compound naming system is still used today. John Dalton
proposed Dalton's law in 1803. This law describes the relationship the makeup in a mixture of gases
and the pressure that each contributes to the mixture. Dalton had also proclaimed in 1803 that all
matter was composed of small indivisible particles. In 1808 he published New System of Chemical
Philosophy where he proposed a modern atomic theory. In this book he made an outline of the
identification of the atomic theory. Dalton claimed that atoms of a given element possess unique
characteristics and weight, and three types of atoms existed. Those three types are simple
(elements), compound (simple compounds), and complex (complex molecules). There were many
uncertainties about Dalton's published book. In 1811, Amedeo
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30. The Science Of The Chemistry
The science of the chemistry was known and developed in ancient Greece. This assignment will
contain a description of key ideas, and important people including explanations of key discoveries,
ideas and their contribution to the accepted theories of today. By 1830 there were more than 50
elements known. In 1934 the element uranium, with atomic number of 92 was found.
Democritus known as to how atoms were created. His ideas influenced on modern science and he is
remembered for his formulation of the atomic theory of the universe. He found Aristotle to be the
biggest contributor to discoveries in natural science. Democritus' main contribution to chemistry
was the suggestion that all matter is made up of particles which he called atoms. He was the first to
create an atomic model and he helped people to understand the idea and helped scientists in the
future.
Robert Boyle, an inventor, employed Robert Hooke to help him with his experiments. They built the
air pump in 1659 which was used in many experiments. Boyle's various experiments helped him
discover relationships between pressure and volume of gases. Boyle made an important contribution
to the development of modern science. He performed assays on gold and silver, and tested for
copper with ammonia, and tested for salt in water with sliver nitrate. Also he is isolated to find four
elements. He was the first person to define the word element in modern understanding. In the time
he define fourteen elements was known
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32. Group 1 Lab Report
The physical properties of group 1: The physical properties of group 1 are that they have low
melting points and boiling points, in addition I would like to say that they all are alkali metals which
means that some of metals will have a lower melting point then the other one. Rubidium and
caesium have one of the lowest melting points which means that they will burn very easily.
However some of these metals have higher melting points than rubidium and caesium which
happens to be lithium.
The chemical properties of group 1: all the elements in the group one have only one electron which
happens to be outer energy level. However group one are white solids and this means that they will
easily dissolve in water. In addition group one are all on the left side of the periodic table which
means that they are all alkali and alkali metals form alkaline compounds. However this will mean
that all the metals have similar properties to one on other.
The physical properties of the 7 elements: The 7 elements are called halogens which mean that they
have low boiling ... Show more content on Helpwriting.net ...
The metals in group 1 if they are melted the metabolic bond will get weaker and weaker this means
that the atoms can move freely, and can also be broken if the boiling point gets reached .Also In
group 1 as you go down the group the reactivity increases this is because the atoms get bigger also
the connection between the nucleus and the electron gets weaker. The only thing that can affect this
atom is the number of layers of inner electrons which will surround the atom. In addition if more
layers of electrons where added this will mean that more space will be taken this is because
electron–electron repulsion. In result, the atoms will increase in size down the
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34. Magnesium Oxide Lab Report
Intro In this lab, we will create a chemical reaction between the reactants oxygen (O2) and
magnesium (Mg) using combustion. The product will be magnesium oxide (MgO). In this lab we
will record the masses of reactants and products to perform stoichiometry of the chemical equation
Mg + O2 –> MgO. The actual yield of product will differ from the theoretical yield based on how
the experiment is performed. The independent variable is the product amounts and the dependent
variable is the percent yield. Literature Review The word stoichiometry originates from the Greek
language (ChemTeam). The Greek words for "element" and "measure," stoicheion and metron, are
what combine together to make that word stoichiometry. When performing stoichiometry, the
masses of products and the masses of reactants involved in the particular chemical equation you are
observing are used in the calculations. The first person to record the concept of stoichiometry was
Jeremias Benjaim Richter, a German chemist. He said, originally in German and translated to
English, "Stoichiometry is the science of measuring the quantitative proportions or mass ratios in
which chemical elements stand to one another." In a typical stoichiometry problem, you will be
given the chemical equation of a reaction, a certain amount of reactant, and then you will need to
find how much of the product can be formed. The skills needed to complete a stoichiometry problem
are balancing equations, converting between grams
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36. What Does The Invention Can Be Made For A Healthier...
Ever wonder what invention can be made that will benefit the present and the future. Yet, it is not
any ordinary invention, it is an invention that will make the planet greener and provide a healthier
lifestyle for the people. These green developments are what are called sustainable chemistry. It is a
tactic created to provide the needs of the present generations that will later also benefit the future
generations. The people have to create greener solutions to many of these environmental problems
because as we know a large portion of our planet is being destroyed piece by piece. From the air we
breathe all the way to the soil, we walk on every day. A major problem would be that many people
are developing major health issues, all because of the filthy air we breathe in. This is all coming
from the toxic gases from factories and cars, toxic chemical waste, overloads of waste, plant
chemicals, the list is endless of how many harmful chemicals are released. Many of these chemical
uses can be decreased if we do our part of creating a situation. Instead of creating more trash and
throwing away piles of garbage into the landfills and getting much of that burned or chemically
proceed. Mostly 30 to 40 percent of food is thrown away into the landfills in just the United States.
We can simply divide our trash and can create compost. Forming a chemical solution created by
pure food compost that is only proceeded by worms. Reducing the use of intoxicated chemicals that
harm the earth's
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38. Neon: A Chemical Element
Neon is a chemical element. Neon was discovered by two chemists named Sir William Ramsay and
Morris W. Travers in the country of England. Ramsay and Travers discovered this element in the
year or 1898. The word "neon" is a Greek word that means "new". Neon was discovered through the
studies of liquefied air. This element belongs to the "noble gases" group in the periodic table. The
symbol for this element is 'Ne'. Neon is in period two. The atomic number of neon is 10. The atomic
mass of neon is 20.1797. There are three known stable isotopes for the element neon. The element
neon is a nonmetal. When at lab temperature, neon is a gas. When at freezing point, neon turns from
a liquid to a solid. When at condensing point, neon turns from a
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40. Physics Of The Periodic Table
The Periodic Table
Chemically speaking, the periodic table was a major factor in improving the study of elements, in
which then the study of these elements expands into broader studies such as atoms and sub–atoms.
This essay will talk about the history of the development of the periodic table and will further
discuss the how and why it was created. Moreover, it will include the history of various chemists
that contributed in the improvement of the table such as Johann Wolfgang Döbereiner, John
Newlands, Dmitri Mendeleev, Henry Moseley, Glenn T. Seaborg.
The periodic table is a tabular arrangement of the chemical elements, organized on the substratum of
their atomic number (number of protons in the nucleus), electron configurations, and ... Show more
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As a result, a periodic table provides an utilizable framework for analyzing chemical manner, and so
the tables, in diverse forms, are widely utilized in chemistry and other sciences.
In 1817, Johann Wolfgang Döbereiner commenced to formulate one of the earliest endeavours to
relegate the elements. In 1829, he found that he could compose some of the elements into groups of
three, with the members of each group having cognate properties. He termed these groups as triads.
Some of the triads that were relegated by Döbereiner are chlorine, bromine, and iodine, also
calcium, strontium, and barium, and sulfur, selenium, and tellurium and finally lithium, sodium, and
potassium. In all of the triads, the atomic weight of the middle element was virtually precisely the
average of the atomic weights of the other two elements.
In 1865, few years after the discovery of the triads, the English chemist John Newlands relegated the
fifty–six kenned elements into eleven groups, predicated on their physical properties. Newlands
noted that many pairs of like elements existed, which differed by some multiple of eight in mass
number, and he was the first to assign them an atomic number. When his 'law of octaves ' was
printed in Chemistry News, likening this periodicity of eights to the musical scale, it was ridiculed
by some of his contemporaries. His lecture to the
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42. Year 12 Chemistry Essay
Year 8 Science Chemistry COMMON ASSESSMENT TASK Outline This Common Assessment
Task assesses your ability to research and present information on a chemical element of your choice.
Mark – 20 Allocation of marks 1. Peer mark for Element Cube = 10 2. Validation test = 10 Date
given – ________________ Date due – ________________ Element Cube Research 1. Under the
direction of your teacher choose an element to conduct your research on 2. Collect data about your
element using reference materials and internet sites. 3. Format your data into 6 'panels', that when
printed on paper are exactly 9.5 cm square. 4. Construct the element cube using the cardboard
template. 5. Glue the data 'panels' collected neatly on to the 6 sides of the cube. Presentation of cube
1. Use of colour, ... Show more content on Helpwriting.net ...
Your name and class eg 8–9 Side #2 – Atomic structure: You must have a picture that shows
the structure of the element (number of protons, neutrons, and electrons) and the shell pattern of the
electrons. Side #3 – Physical & Chemical Properties Include five pieces of information that is
appropriate to your element eg ◦ Colour: ◦ State of matter at room temperature: ◦ Density: ◦ Melting
point: ◦ Boiling point: ◦ Odour / Texture / Hardness: ◦ Flammability: ◦ How reactive is it? (Will it
combine with other elements?) Side #4 – Periodic Table Information: Include the following five
pieces of information that is appropriate to your element: ◦ Type of Element: ◦ Atomic Number: ◦
Atomic Mass: ◦ Period Number: ◦ Group Number: Side #5 – About Include information that is
appropriate to your element eg ◦ Background history of your element. ◦ Origin of the name ◦ Who
discovered or first identified your element? ◦ What country was it found in? ◦ When was it
discovered? ◦ Where is your element found and how is it
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44. The Impacts Of John Dalton And The Atomic Theory
John Dalton and the Atomic Theory John Dalton was an English chemist, meteorologist and
physicist. John Dalton was one of the first scientists to use homemade instruments to make weather
observations. He recorded over 20,000 weather observations over a period of 57 years,(Retrieved
from Infobase Learning). His fascination for the weather and atmosphere pursue him to research the
nature of gases, which in turn lead him to his biggest accomplishment. He built the atomic theory,
after two centuries, this theory still remain valid in the field of modern chemistry. John Dalton is
considered to be the father of modern atomic theory.
John Dalton Pursues Chemistry John Dalton a Quaker kid didn't receive a formal education in his
childhood. However, he got a basic grounding in reading, writing and math in a Quaker school. John
Fletcher a teacher in the school inspired the young to solve mathematical problems, a skill John
Dalton quickly mastered. Elihu Robinson became interested in the ... Show more content on
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He considered that gases must be made up of particles that can somehow occupy spaces between
particles that make up water. Also, that in a mixture of gases the different particles must intermingle
rather than separate into layers depending on their density. Dalton performed experiments to test and
correct his atomic theory. As every scientist John Dalton makes mistakes. He made a mistake in
assuming that the simplest compound of two elements must be binary, formed from atoms of each
element in a 1:1 ratio. This postulate prevented his theory from being accepted for many years.
Many of the atomic weights were incorrect and later corrected. For example, he said oxygen atomic
weight was seven instead of eight. Although he committed little mistakes, Dalton's theory provided
a logical explanation of concepts, and led the way into new fields of experimentation.
How does The Atomic Theory Affects
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46. Dalton 's Atomic Theory ( 1803 )
Dalton's atomic theory (1803):
Dalton proposed that all matter is made of atoms (tiny indivisible particles), which cannot be
destroyed. He visualised atoms as a solid particle without a structure. All atoms of an element are
identical in mass and properties. The atoms of one element differ from the atoms of all other
elements in atomic weight. Compounds are combinations of two or more different types of atoms. A
chemical reaction results in the rearrangement of atoms in the reactant and product compounds and
they don 't destroy or create atoms.
Thomson's plum pudding model (1909):
Thomson discovered electron in 1897, which allowed him to develop a new atomic model. In
Thomson 's model, the atom is composed of electrons surrounded by a positively charged fluid
which balances the electrons ' negative charges, like negatively charged "plums" which are
surrounded by a positively charged "pudding". Thomson thought the electrons were positioned
throughout the atom in rotating rings. The atom was also sometimes described to have a "cloud" of
positive charge.
Rutherfordian atomic model (1911):
Rutherford's discovery of the nucleus allowed him to develop a new atomic model, the planetary
model. In this model, the centre of the atom is the nucleus. The nucleus contains most of the mass
and all of the positive charge of the atom. Electrons circle around the nucleus like planets do around
the sun. Positive protons in nucleus and electrons in orbit around nucleus.
Bohr's shell
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48. Analysis Of The Book ' The Chemy '
A Chemy called Al is a very outgoing book that helps you use your imagination so you can clearly
see the different forms of elements of the periodic table. It 's full of action and will keep you
guessing on what is going to happen. Here are some main key points of the story.
Key idea 1
Chemy lion is one of the main characters In the book "The Chemy called Al" he is supposed to
represent something big and luxurious and mysterious. In the book Chemy lion blends in with the
surrounds around him. Almost like a chameleon. Alchemy was a kind of pre science that existed
from a bout 500 B. C. to about the end of the 16th century. People who studied alchemy–
alchemists– wanted to find a way of changing lead, iron, and other metals into gold. They were also
looking for a way to have eternal life. Alchemy contained too much magic and mysticism to be a
real science, but alchemist developed a number of techniques and produced many new materials that
were later found to be useful in modern day Chemistry. He represents Albertus Magnus. Albertus
Magnus was a saint in the 1200s. He was also a scientist.
Key idea 2
The periodic are horses. They represent different elements on the periodic table. For example, Au,
which is gold is a chemical element. Its atomic number is 79. In its purist form it is a bright, slightly
reddish yellow, soft, dense and a ductile metal. Chemically gold is a transition metal and a group 11
element. Each horse is a different size, shape, and
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50. History And Development Of The Periodic Table
History and Development of the Periodic Table
Ben Madden
10B
Part A: Timeline of the Periodic Table
0
Ancient Greeks believed that everything was made of four elements mixed together in different
proportions. These elements were fire, water, air and earth.
1661
Robert Boyle had an assumption that an element was an individual substance that could not be
broken down further into a smaller substance through the process of a chemical reaction. Boyle's
assumption is considered to be the beginning of modern chemistry.
1789
Antoine Lavoisier created a list of substances that he considered to be elements. He separated his list
of 33 elements into metals and non–metals. Some items on the list were classified as compounds
because they could not be determined to be otherwise, because of the lack of technology and
equipment available at the time.
1820
Jakob Berzelius began to replace the patterns which represented chemical symbols with
abbreviations for the element. He developed a system of organisation based on the weight of an
element, with hydrogen having a value one, and all other elements having a higher value. He used
one universal system.
1829
More chemists began studying elements and their properties. Johann Dobereiner identified 40
elements and noticed similar properties between the elements. He noticed that different groups of
elements had a similar atom structure.
1864
John Newlands identified that every eighth element had a similar structure and came
53. Evaluate Dalton's Theory
1.Obtain, evaluate, and communicate information about the use of the modern atomic theory and
periodic law to explain the characteristics of atoms and elements.
Dalton had come up with the atomic theory which said "that all matter is made of atoms, all atoms
of a given element are identical in mass and properties, compounds are combinations of two or more
different types of atoms, and a chemical reaction is a rearrangement of atoms." we learned so much
from this theory, we know that the atoms are not indivisible because they are made up of protons,
neutrons, and electrons and we know that Daltons picture of the atom was different than what it
actually is. The periodic law says that "physical and chemical properties of the elements recur in ...
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Use the periodic table as a model to predict the relative properties of elements based on the patterns
of electrons in the outermost energy level of atoms (including atomic radii, ionization energy, and
electronegativity of various elements). With the Atomic radii we can't figure out the atomic radius of
the atom because there is not a zero probability for finding the electron. Because of this we cannot
figure out the exact distance. All that we can figure out is the distance between two nuclei and we
use the formula "1 nm = 1 X 10–9 m; 1 pm = 1 X 10–12 m." Ionization Energy is the energy that is
required to fully remove an electron from an atom or ion. Electronegativity is the ability to attract
electrons to an element
6. Plan and carry out an investigation to gather evidence to compare the physical and chemical
properties at the macroscopic scale to infer the strength of intermolecular and intramolecular forces.
Intermolecular forces are forces that do interaction between molecules, such as: forces of
attraction,or repulsion. These are the ones that will act between molecules. Intramolecular forces are
forces that help hold the atoms together which make up a molecule or
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55. The Scientists : The Physicists
Summer Reading Quiz: The Experimenters, Twelve Great Chemists
The Experimenters goes in depth into the lives of twelve great chemists. Chemistry had been apart
of our world since the beginning of time. Chemistry explains why the sky is blue and what makes up
our very existence. The twelve chemists discussed in this novel include Antoine Lavoisier, Joseph
Priestley, Jons Jacob Berzelius, Justus von Liebig, Dmitri Mendeleyev, Louis Pasteur, Marie and
Irene Curie, Linus Pauling, Richard Willstatter, and Dorothy Crowfoot Hodgkin. Each chapter starts
at their birthplace and will take you through the life of the chemist, from greatest discoveries to
personal relationships. You will read about the struggles and breakthroughs each chemist ... Show
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Even though he is gone, his discoveries still live on to this very day.
Joseph Priestley is known as the diligent experimenter and furious free thinker. Priestley was the
founder of pneumatic chemistry, the chemistry of gases. He was also the inventor of carbonated
water. Priestley also discovered what we today call photosynthesis. He also found "nitrous air" or
nitrous oxide; "diminished nitrous air" or nitrous which is now known as laughing gas, a useful
anesthetic; "acid air" or hydrochloric acid; "alkaline air" or ammonia; "vitriolic acid air" or sulphur
dioxide. Last but not least, his most important discovery of all time, his discovery of oxygen, which
he called "dephlogisticated air." He had discovered the gas which is the most abundant element in
the Earth's crust and makes up one–fifth of its atmosphere.
John Dalton, also known as the Quaker Atomist, developed the widely known Chemical Atomic
Theory. His ideas for this theory can be easily stated. All elements are made up of tiny invisible
particles and that these particles, following Heraclitus, would be called "atoms." All atoms of a
given element are chemically identical. Atoms cannot be destroyed or created during chemical
reactions, although atoms of different elements may combine to form compounds. The chemical
reaction forming a compound does not involve a change in atoms, it involves a change in
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57. Questions On The Periodic Table
INTU Statement
I need to understand the various arrangements of elements and its similarities to the periodic table
given in the Nelson Chemistry 11 textbook.
Periodic Table
The periodic table is the chemicals arranged in order of increasing atomic number and grouped with
similar chemical properties. There are 7 periods and 18 groups in the periodic table. The periodic
table used in the textbook has a total of 118 elements.
About Dmitri Mendeleev Dmitri Mendeleev also known as the Russian scientist who was born in
Tobolsk, Siberia. Mendeleev was one of 17 children in his house hold. He is known for the periodic
table we use today which was created in 1869. Although at the time he only had 65 elements, his
periodic table was the one that stood out the most with, elements organized in increasing atomic
weight and grouping them by similarity of properties. Throughout the years more and more elements
were being discovered and in total there are 118 elements. What Dmitri did to discover the periodic
table was that he wrote all of the 65 elements on separate cards and wrote the atomic weight along
with the properties. He re–arranged the cards so that he could find a pattern which he did and wrote
it on a piece of paper. He later on published the periodic table in the Principles of Chemistry in
1869. Dmitri also received many awards one example was the Chair of General Chemistry at the
university of Saint Petersburg.
Alternative Proposal ( answering question 10 on pg 33)
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59. History of the Science of Chemistry Essay
The history of chemistry makes a span of time reaching from ancient history to the present. By 1000
BC, ancient civilizations used technologies that would eventually form the basis of the various
branches of the subject. Examples include extracting metals from ores, making pottery and glazes,
fermenting beer and wine, extracting chemicals from plants for medicine and perfume, rendering fat
into soap, making glass, and making alloys like bronze.
The science of chemistry, alchemy, was unsuccessful in explaining the nature of matter and its
transformations. However, by performing experiments and recording the results, alchemists set the
stage for modern chemistry. The distinction began to emerge when a clear differentiation was made
between ... Show more content on Helpwriting.net ...
He was the youngest son in a family of fourteen children. At the age of eight, after private tuition at
home, he was sent for several years to Eton, which the sons of gentlemen were just beginning to
attend, and then, at the age of twelve, to the Continent with his next older brother, Francis, later
Lord Shannon. There a citizen of Geneva tutored him privately in the polite arts, the conventional
subjects of a liberal education, and practical mathematics; then, or in the course of his subsequent
travels, he was introduced to the new science, including Galileo's Dialogue on the Two Chief World
Systems, which he read in Florence in 1642. He was
How did natural resources limit or advance my topic. One reason it advanced my topic is the
creation of the periodic table and the history and how it has impacted the world. The table contains
the currently identified chemical elements arranged based on their chemical properties. Elements
have certain properties and tendencies to react that were found to repeat periodically when elements
of increasing atomic masses were compared.
Each cell of the table contains a different element. The cells of most periodic tables contain the
name and symbol of each element, the atomic number (the number of protons, and the atomic
weight (average number of protons + neutrons. Some periodic tables will contain other information,
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61. Chemical Element Essay
Element: Lithium
Lithium and Its Basic Characteristics
The chemical element Lithium (Li) has an atomic number 3and is the first member of the Alkali
metal family. This element is also the least dense of all the metals – about half of the density of
water. Lithium is a very soft silvery metal that has a melting point of 180.54˚c and a boiling point of
1,335˚c. This is an active element but nit as active as the other Alkali metals. This element reacts
slowly on a water having a room temperature and rapidly at high temperatures. Also, lithium reacts
with most acids that gives off hydrogen gas but does not react with oxygen. Under conditions,
lithium is combined with sulfur, hydrogen, nitrogen and halogens. There are two naturally occurring
isotopes; ... Show more content on Helpwriting.net ...
In his studies, he could not identify 10% of the mineral. He then concluded that the missing 10%
must be a new element. He called the element "Lithium", from the greek word Lithos which means
stone. He was not able to produce lithium. About a year later, however, Swedish chemist William
Thomas Brande (1788–1866) and English chemist Sir Humphry Davy (1778–1829) were both able
to extract the pure metal from its compounds.
Occurrence or Relevance in Nature
The abundance of Lithium in the Earth's crust is estimated to be about 0.005 percent that places it
among the top 15 elements found here in Earth. Aside from spodumene, petalite, and lepitdolite,
lithium is also obtained from saltwater. Lithium metal as well as its compounds have great uses.
Two of the most significant applications are in the Glass and ceramic field and in the production of
aluminum. The first commercial use of aluminum was in the production of alloys early lithium
alloys included lead and were used to make tough ball bearings for machineries.
Trivias/ Fun Facts
– The largest producer of lithium is the United States. Three of the largest U.S. mines are located in
the Silver Peak, Nevada, and Kings Mountain and Bessemer City, North
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63. The Chemical Element Of Uranium
Background
Uranium (U) is a chemical element; it is a silvery–white metal. It is one of the heaviest of all the
naturally – occurring elements. It was discovered in 1789 by Martin Klaproth, it was named after the
planet Uranus, which was discovered eight years earlier. Uranium can be found naturally in small
amounts in rocks, air, soil and water.
PHYSICAL AND CHEMICAL PROPERTIES
Atomic number 92
Atomic mass 238.03 g.mol –1
Density 18.95 g.cm–3 at 20°C
Boiling point 3818 °C
Melting point 1132 °C
Isotopes 11
Electro–Negativity according to Pauling 1.7
Uranium is hard, malleable and ductile. Uranium metal has a very high density. It is very reactive so
cannot be found in the environment in its elemental form. When finely divided, it can react with
cold water. In air it is coated by uranium oxide, tarnishing rapidly. It is attacked by steam and acids.
It has the ability to form solid solutions and inter– metallic compounds with many metals. While
Uranium is not hazardous by itself, some of its by–products and decay products pose a huge threat
upon build–up.
Uranium is weakly radioactive due to its unstable isotopes; again it has gained importance in the
generation of Nuclear energy. It is of great demand in the production of bullets, missiles and bombs.
It is also used to fuel power plants by enriching it with the uranium–235 isotope. The isotope
uranium 238 is used to estimate the age of rocks and also used for radiometric dating. Other
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65. 3a Lab Report
Ka Bae Ly Chemistry 3A Lab Julie Steele, Monday 8am 9 October 2016 Essay #1 Chemistry is
composed of many molecules and changes of properties in the matter of science. The elements on
the periodic table arranged from metal to non metals, plays an important role when it comes to
making a compound and mixture. Each of the element have their own unique atomic mass which
matters when it comes to organizing the periodic table and when there is a calculation. There are lots
of importance about the atomic mass of each element that will be discussed later in this essay. An
experiment performed using the mass of zinc and copper has determined whether which element
have excess remaining. Will there be a difference if an alkali metal was used? An ... Show more
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Although there are some differences, the chemical formulas still rely upon the metals and non
metals on the periodic table. Molar mass is a method that concludes the weigh of a substance in a
chemical formula. It makes the calculation of the chosen composition easier by breaking it down to
grams per mole. Referring to experiment 4, there are many metals that can't be mixed in an aqueous
solution because it can result into a combustion. However, alkali metals are not single atoms so it
will certainly have an atomic weight and ratio to determine if there's any excess of the
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67. Environmental Pollution is Causing Serious and Lasting...
One of the greatest problems that the world is facing today are of environmental pollution, pollution
is increasing rapidly every year and causing serious and lasting damage to the earth. In the short
story "A Fable for Tomorrow" by Rachel Carson, describes a small beautiful town in America that
later become a terrible town, because it was overwhelmed by pollution. In addition, most of the
technology that is uses in today society causes pollution for examples, cars, and pesticides.
However, it is very difficult for people to give up on technology, since they are very used of using
every day that makes it challenging to protect the environment. It is a similar story "Our Animal
Rites" by Anna Quindlen, shows how nature is harmed because of ... Show more content on
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In addition, due to the expansion of modern agricultural technology, farmers tend to use a lot of
chemical fertilizers and pesticides to increase the harvest. Many burning processes, such as wood
and coal fires, wood stoves, and the burning of fuel in cars harvest tiny elements of carbon, in the
form of smoke. These may affect climate change by dropping the clearness of the atmosphere. There
are not a lot of people who are willing to give up things that cause carbon dioxide pollution in order
to protect the environment. People think if they do give on everything that produces carbon dioxide,
that cause pollution they will not have enjoyment in their life, which makes hard for people to live
in harmony with nature. Moreover, it becomes a big challenge for people to give up on something
that is very useable in everyday life such as cars, and rail because if they do not use car to go
somewhere they have to walk, which takes a lot of their. The other reason they do not want to give
up on their things is more responsibility and less leisure time to enjoy.
Another thing that is becoming a challenging to protect the environment is agricultural technology
that is causing pollution in the
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69. Periodic Trends Of Chemical Properties
Periodic Trends of Chemical and Physical Properties in Group 1A and 7A
Hamish Thomson, Chemistry 11.2, Mr Ryan O'Sullivan
Intro:
In chemistry, there are two classes of observable properties matter can display; chemical and
physical. These properties are classified by what needs to happen to the substance before the
property becomes evident. Chemical properties require a chemical change while physical properties
don't need a chemical change to occur. Four properties of the alkali metals and halogens will be
talked about through this essay, two chemical and two physical. The two chemical properties will be
reactivity, how willing a substance is to undergo a chemical change and toxicity, the ability of a
substance to cause damage to an ... Show more content on Helpwriting.net ...
In Fig 1 the reactivity of Non–Metals decreases every period and increases every group, the
halogens lie on the end of the group of Non–metals causing them to be highly reactive. The alkali
metals have a single electron in their outer electron shell, making it easy for them to become a noble
gas and period down the periodic table the easier it is to get rid of the extra electron, causing the
alkali metals to become more reactive the further down the periods. To become a noble gas a
halogen must gain an electron, the farther away the outer shell is from the nucleus, the more energy
that is required for an electron to enter the shell. Halogens need one more electron to become a
noble gas, while alkali metals need to donate an electron to become a noble gas. (Johnsonburg High
School, n.d.) Fig 1. This shows the trends of the reactivity of Metals and non–metals on the periodic
table.
Paragraph 3. Toxicity
Toxicity is how dangerous a substance is to an organism, it is commonly measured by the amount
required to kill 50% of the population of a given organism. The toxicity of the alkali metals
increases each period, due to the increase in reactivity. The toxicity of the halogens decreases as you
go down until astatine, which is harmful due to radioactivity (Helmenstine, 2017).
Paragraph 4. What is a physical property:
A physical property is a property of matter that can be observed without causing a
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71. Atomic Structure Research Paper
Atomic structure In the nucleus of an atom there are protons and neutrons the number of protons and
neutrons depends on the element and ,if it is an isotope of that element. E.g. carbon 12, carbon 12
has six neutrons six protons and 6 electrons . Electrons are located around the nucleus of the atom.
Electrons are in shells, the shell closest to the nucleus is 1 , the one after 2 and so on. Each shell can
only hold up to a certain number of electrons . the first can hold up to 2 , the second 8 (2+6) the
third up to 18 (2+6+10). The general formula for finding out how many electrons a shell can hold is
2n^2. Electrons have a negative charge , while protons have a positive and neutrons have no charge.
A atom has the same number of protons and electrons. An ion is formed when an atom loses or gains
a electrons .
Radioactivity is when energy is emitted from the nucleus due to the nucleus being unstable. The 3
types of radiation are Alpha ,Beta and gamma. Alpha particles have 2 protons and two neutrons.
Examples of radioactive nuclei that emit alpha radiation. Are : uranium, thorium, actinium, and
radium They are very ionising so they give energy off onto whatever they are in contact with.
Therefore, it loses energy more quickly. They are not very penetrating so can be stopped by a piece
of paper or skin. Beta particles have 1 ... Show more content on Helpwriting.net ...
isotopes have the same chemical properties as their elements but different chemical properties. This
is because isotopes of an element have the same number of electrons as an atom of that particular
element. The electron arrangement is what affects chemical properties, and isotopes have the same
electron arrangement , so they have the same chemical properties. However the have a different
number of neutrons which changes the mass number. The mass number is what determines the
physical properties , such as boiling point and
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73. Boundless Fluorine Essay
Introduction The elemental group F, Cl, Br, I, and At, located in the seventeenth column of the
periodic table, are known as Halogens. Halogens are nonmetals and they have an effective nuclear
charge, because of this they're highly electronegative. Due to their electronegativity, they're very
reactive and they gain electrons through reactions with other elements. However, halogens can be
very harmful or deadly to biological organisms. Physical properties of Halogens When the electron
shells are filled, the atoms get bigger as you go down the group of halogens. When fluorine is a
diatomic molecule, the F–F bond is quite weak (Boundless. "Halogens." Halogens | Boundless ...
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The color of this element reflects the reactivity of it. The appearance is a very pale yellow–green.
This element is a dangerously reactive gas. In fact it's one of the most reactive of all the elements
and reacts mostly to metals. An example of this is when steel wood is exposed to fluorine it bursts
into flames ("Fluorine – Element Information, Properties and Uses | Periodic Table." Royal Society
of Chemistry). Which also explains why they used fluorine in the Second World War to help develop
the atom bomb and other projects having to do with that. It's also been used to help make gases for
high powered transformers. It's also used in teflon, cable insulation, plumbers tape, and a base for
waterproof shoes and clothes. Chlorine has a similar look to fluorine. Chlorine is a yellow–green
dense gas. It has a very distinct smell to it and has been used as a chemical weapon. It also kills
bacteria and is used as a disinfectant. Chlorine disinfects drinking water and swimming pool water
and is also used in organic chemistry. It can be used as an oxidising agent and in substitution
reactions. But in the past it was used to make chloroform. Since chlorine is poisonous it was used as
a chemical weapon during World War
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75. Argon Research Paper
Dav'Eyoine Camp
Mr. Irwin 7th
February 9, 2016
My Element Argon My element is Argon and its symbol is Ar. Argon is the third most common gas
that is found in the earth's atmosphere. Argon is a noble gas that is also used to keep light bulbs from
bursting. Argon is located in period 3 group 18. Argon is also used to make titanium and other
reactive chemicals. Argon is an odorless, colorless gas. Argon is the 3rd most abundant gas. Argon
has 8 protons, 8 electrons and 2 neutrons in its shell. Argon was discovered by 2 men named
William Ramsey and Lord Rayleigh, they said argon is made when nitrogen and oxygen come to
gather. Argon is classified as a nonmetal and begins to compose when it warms to –411 degrees
Fahrenheit. At room temperature
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77. Elements Of A Chemical Reaction Lab Report
Chemical Reaction Lab Report The purpose of this experiment is to determine why the distance
between beaker A and beaker B increase or decrease the amount of visible vapor. An acid–base
neutralization reaction is a chemical reaction between an acid and a base. Evidence of a chemical
reaction is that a gas is formed. I noticed that a thicker, denser gas was formed when beaker A and B
were right next to each other as opposed to when they were about a meter apart. If an acid–base
neutralization reaction is related to vapor, then as the distance between beakers A and B decrease,
the amount of vapor will increase due to a reaction between beaker A and B's gases. To begin with, I
started with two 250 mL beakers about one meter apart. Beaker A was
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79. Potassium: A Chemical Element On The Periodic Table
Potassium essay Potassium is a chemical element on the periodic table with the symbol K from
Neo–Latin, Kalium. Potassium comes from the alkali metals family on the periodic table and has
one valence electron. It has 20 neutrons,19 protons and the same amount of electrons . It has an
atomic number of 19 and an atomic mass of 39.0983. Its Melting point is 146.08 degrees and it's
boiling point is 1,398 degrees. In room temperature potassiums phase is solid. The second most
dense metal after lithium is potassium, It is a soft solid and can be easily cut with a knife. Potassium
begins to tarnish toward gray immediately on exposure to air. Potassium is a silvery gray color but
when mixed with water it explodes with a purple flame. Potassium is ... Show more content on
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Most people use potassium compounds to create things such as potassium soap. Potassium ions are
helpful for all living cells to function. Fresh fruits and vegetables are good dietary sources of
potassium. It cost about $100 for 100g of potassium. You can find potassium in food such as
bananas, avocados, cooked spinach, potatoes, oranges, apricots, and prunes. Potassium is necessary
for proper function in your body system and is one of the top electrolytes in your body. Potassium is
a role in regulating fluid levels in your body. The electrolyte works to balance in you blood cells,
manage your blood pressure, and keeps your heart functioning. Potassium also helps in your nervous
system by helping in the correct function of tissues for nerve impulses. But potassium also has some
bad effects as well. It can lead to bad physical and mental problems. Insomnia, anorexia, and
depression are some mental side effects. Poor reflex, kidney failure and heart attack are some of the
physical effects that potassium can do. There are some reasons to why you could activate these
potassium symptoms such as excessive alcohol, poor overall health, high stress, and long period of
vomiting. All of these things can make your potassium level drop quickly. The best way to keep a
stable potassium level is to eat fruit and
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