ike the other alkali metals, lithium has a single valence electron that is easily given up to form a cation. Because of this, it is a good conductor of heat and electricity as well as a highly reactive element, though the least reactive of the alkali metals. Lithium's low reactivity compared to other alkali metals is due to the proximity of its valence electron to its nucleus (the remaining two electrons are in lithium's 1s orbital and are much lower in energy, and therefore they do not participate in chemical bonds).
Lithium metal is soft enough to be cut with a knife. When cut, it possesses a silvery-white color that quickly changes to gray due to oxidation. While it has one of the lowest melting points among all metals (180 °C), it has the highest melting and boiling points of the alkali metals.
Lithium has a very low density of 0.534 g/cm3, comparable with that of pine wood. It is the least dense of all elements that are solids at room temperature, the next lightest solid element (potassium, at 0.862 g/cm3) being more than 60% denser. Furthermore, apart from helium and hydrogen, it is less dense than any liquid element, being only 2/3 as dense as liquid nitrogen (0.808 g/cm3).[note 1][5] Lithium can float on the lightest hydrocarbon oils and is one of only three metals that can float on water, the other two being sodium and potassium.
Lithium floating in oil
Lithium's coefficient of thermal expansion is twice that of aluminium and almost four times that of iron.[6] It has the highest specific heat capacity of any solid element. Lithium is superconductive below 400 μK at standard pressure[7] and at higher temperatures (more than 9 K) at very high pressures (>20 GPa)[8] At temperatures below 70 K, lithium, like sodium, underg...
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...um than they should, and some younger stars have far more. The lack of lithium in older stars is apparently caused by the "mixing" of lithium into the interior of stars, where it is destroyed. Furthermore, lithium is produced in younger stars. Though it transmutes into two atoms of helium due to collision with a proton at temperatures above 2.4 million degrees Celsius (most stars easily attain this temperature in their interiors), lithium is more abundant than predicted in later-generation stars, for causes not yet completely understood.
Though it was one of the three first elements (together with helium and hydrogen) to be synthesized in the Big Bang, lithium, together with beryllium and boron are markedly less abundant than other nearby elements. This is a result of the low temperature necessary to destroy lithium, and a lack of common processes to produce it.[34]
Liopleurodon lived in ocean which covered the Europe at that time. There were two species of Liopleurodon which lived in Jurassic Period.
There are many physical properties of neon, such as the fact that it is colorless, odorless, and tasteless. Also, neon is lighter than air. With a density of density 0.89990 g/liter. The freezing point of neon is -248.67° C, and the boiling point of neon is -246.048° C, which is even lower than the boiling point of nitrogen (-195.8°C). When under low pressure, neon emits a bright orange-red glow if a small electric current is passed through it. The electron configuration of neon is 1s22s22p6. The chemical properties of neon include the fact that it is not reactive because it has a full outer shell, and therefore cannot gain or lose any electrons. Because of this, neon belongs to a group of elements called "noble gases." These are all gases which have a full outer shell and cannot react in nature. The period of neon is 2, and the group is 18.
The Big Bang, the alpha of existence for the building blocks of stars, happened approximately fourteen billion years ago. The elements produced by the big bang consisted of hydrogen and helium with trace amounts of lithium. Hydrogen and helium are the essential structure which build stars. Within these early stars, heavier elements were slowly formed through a process known as nucleosynthesis. Nucleosythesis is the process of creating new atomic nuclei from pre-existing nucleons. As the stars expel their contents, be it going supernova, solar winds, or solar explosions, these heavier elements along with other “star stuff” are ejected into the interstellar medium where they will later be recycled into another star. This physical process of galactic recycling is how or solar system's mass came to contain 2% of these heavier elements.
Native Silver, or more commonly know as just “silver,” is a mineral that is created from the element silver (also called Argentum; abbreviated on the periodic table as Ag). It is seldom found as a native element mineral. Instead, it has tendencies to mix together with other minerals such as quartz, gold, and copper.1 11 Silver is actually not really reactive. It is even considered one of the “noblest” of the transition metals, noblest meaning “least chemically reactive.”5 In fact, it is used in many dishes as a fancy garnish that is able (and sometimes meant) to be eaten. Native silver also has one of the highest conductivity rates, both electrical and thermal, of metals. Because of this property, it is used in many electronic circuits as a thin coating.5 Due to its shiny, lustrous quality, native silver is also used for jewelry, decorations, and ornaments.
A huge fascination of arsenic started in the 19th century when people got word of a province in southeastern Austria where people ate arsenic. Women would eat arsenic to help gain weight and fix their complexion to look more beautiful and men would eat arsenic because they believed it helped them breath easier when they were climbing high up in the mountains. One doctor by the name of Dr. Robert Craig MacLagan, was particularly interested in this and visited the town to see for himself what was really occurring. He observed the people and tested their urine to prove that they have been indeed ingesting arsenic. He wrote about the things he witnessed in the Edinburgh Medical Journal. The men in the town would eat 6 grains/dose at least twice a week, sometimes eating it on their bread or just drinking it with their water. As a result many Victorians began self-medicating themselves with arsenic.
Review the effects of arsenic as a soil pollutant on human health. You need to consider the major sources of arsenic (both natural & man-made), pathways for uptake by people and the impacts on human health.
The mixed alkali effect in the glass materials has been the subject of study in the recent years. Many properties of glasses show non linear behaviour of exhibiting a minimum or maximum, as a function of alkali content, if one of the alkali ions is gradually replaced by another alkali keeping total alkali content constant. This behaviour is called mixed alkali effect. The general formula for mixed alkali oxide glass is y[x.A2O + (1-x) B2O] + (1-y) glass former, where A and B are alkalis. The extent of departure from linearity, the direction of variation (positive or negative) depends on the property examined and the glass system. The behavior of mixed alkali effect is independent of glass forming oxides. It is being observed in silicates, borates, phosphates, germanates, tellurites, boro alluminate, alumino silicates, borotellurate etc., glasses. It is also observed that properties related to cationic movement are more sensitive to mixed alkali effect [1-3].
In an “electrolytic solution”, if two electrodes, one being positive and the other negative, are placed in the solution then ions have the ability to transport free electrons to and from both of the electrodes. Acids in a solution are good electrolytes since the acids supply the solution with hydrogen ions. If a solution contains organic compound has sugar or starch, then that solution won’t conduct electricity well since organic compounds are contributing as many hydrogen ions as acids. The most familiar electrolytes would be elements such as potassium, calcium, sodium, and magnesium. Lithium-ion batteries are commonly used in many household as a source of energy, however the battery relies heavily on liquid electrolytes which are flammable and are prone to fires.Researchers at Oak Ridge National Laboratory has created a solid electrolytes that is made out of lithium triphosphate to try to overcome the safety issues presented by lithium-ion
Finding use in “spacecrafts, pacemakers, underwater systems, electric automobiles, and remote monitoring systems” (source 6), the atomic battery has existed for over a century and is growing to benefit our world. The atomic battery generates electricity from a nuclear reaction, utilizing the radioactive decay of specific elements. The atomic battery is certainly not meant for households or as a source of common battery use, but rather powerful equipment needing to run for long, extended periods. Atomic batteries are quite expensive, but can provide an immense amount of energy that will conduct over an extremely long life period. This paper will explain the basic functioning of an atomic battery, investigate a brief history of the atomic battery, and also examine one aspect of energy conversion within atomic batteries, thermal converters.
Lithium-Ion Batteries are extremely popular in the technology industry for several reasons. First off, they are much lighter then other batteries because they are made with lightweight lithium (a light and reactive metal) and carbon. Second of all, they give the most power per pound. A Lithium-Ion Battery stores 150 watt-hours per kilogram. Compare that with a Nickel-Metal Hydride Battery which only has 100 watt-hours per kilogram or a Lead-Acid Battery which only has 25 watt-hours per kilogram. There is simply no comparison, the Lithium-Ion Battery has the most watt-hours per kilogram (Howstuffworks, 2009).
Each scientist or team of scientists had so much trouble reducing the Lithium compounds because Lithium does not exist in its elemental form in nature. It combines very easily with other elements. Lithium is a soft silvery-white lustrous metal, which can be easily cut with a knife, and it is the lightest of all known metals. It is highly reactive with water and air, and tarnishes readily when exposed to the latter due to a formation of a layer of Lithium suboxide on its surface. Because of its high rate of reaction to air, it must be stored under liquid paraffin, oil, or kerosene, which contain no air, to prevent oxidation. Lithium is detected in its compounds by the characteristic red coloration that it imparts to flames when burned, as Gmelin detected, and by spectroscopic methods.
Lithium-ion batteries are the most accepted battery for portable equipment such as laptops and cellphones. The density of these batteries is normally twice that of nickel-cadmium making them more desirable for portable devices. The chemistry of these batteries is better for the environment because it causes nearly no harm when disposed of.
* In method (1), due to the oil that lithium is stored in, not only
Aluminum is a lightweight, silvery metal. The atomic weight of aluminum is 26.9815; the element melts at 660° C (1220° F), boils at 2467° C (4473° F), and has a specific gravity of 2.7. Aluminum is a strongly electropositive metal and extremely reactive. In contact with air, aluminum rapidly becomes covered with a tough, transparent layer of aluminum oxide that resists further corrosive action. For this reason, materials made of aluminum do not tarnish or rust. The metal reduces many other metallic compounds to their base metals. For example, when thermite (a mixture of powdered iron oxide and aluminum) is heated, the aluminum rapidly removes the oxygen from the iron; the heat of the reaction is sufficient to melt the iron. This phenomenon is used in the thermite process for welding iron .
Superconductivity, a similar phenomenon, was discovered in 1911 by Dutch physicist Heike Kamerlingh Onnes. When he cooled some mercury down to liquid helium temperatures, it began to conduct electricity with no resistance at all. People began experimenting with other metals, and found that many tranisition metals exhibit this characteristic of 0 resistance if cooled sufficiently. Superconductors are analagous to superfluids in that the charges within them move somewhat like a superfluid - with no resistance through sections of extremely small cross-sectional area. Physicists soon discovered that oxides of copper and other compounds could reach even higher superconducting temperatures. Currently, the highest temperature at wich a material can be superconductive is 138K, and is held by the compound Hg0.8Tl0.2Ba2Ca2Cu3O8.33.