The poor reactivity of the element is also illustrated by the fact that lithium cannot replace weekly acidic hydrogen from phenyl- acetylene but other alkali metals liberate hydrogen from this chemical compound. It burnt in air or oxygen to form Li 2O and a trace amount of Li 2O 2 but it reacts with nitrogen slowly at room temperature and rapidly to give ruby red crystalline solid Li 3N. Therefore, at 25 ☌, water reacts with lithium very slowly, sodium reacts vigorously, and potassium, rubidium, or cesium react with an explosion. The reactivity of the alkali family increases from lithium to cesium, except nitrogen molecule. In solution, the Li+ion stabilizes by high solvation energy. The large difference between the first and second ionization energy of lithium suggests that the preferred oxidation state of the metal describe by +1 oxidation state or the major chemistry describe by the form of Li+ion. About 1000 tonnes of lithium metal and several thousands of salts are prepared annually for various purposes of use. The major commercial form of the metal like lithium carbonate, Li 2CO 3, produced from ores or brines by different processes and uses largely in the chemical industry. Due to electropositivity, alkali metals readily react with water and cannot be produced by electrolysis but fused chloride and hydroxide are used for the preparation of lithium and sodium. The alkali metals beings most electropositive and never found in nature in elementary states.
In the 19th century, the United States was the largest producer of chemical elements and compounds like lithium carbonate, Li 2CO 3 but in this century, Australia, Chile, and Portugal are the largest commercial suppliers of the metal or compound. Searles Lake in California is an important source of nearly dry and alkaline ( pH scale = 9.5) lithium metal. It also occurs in many springs and some radioactive decay minerals like carnallite, ashes of planets, in taboo, milk, and blood of living animals.
The very low terrestrial or cosmic abundance of lithium compared to other alkali metals describe by its small nuclear charge and low potential barrier which may be facilitated nuclear reaction to heavier elements like beryllium or boron. The aluminum silicate is the main minerals occurs in the form of spodumene, LiAl(SiO 3) 3 about 2.5 to 3 percent and lepidolite, LiF, LiOH, Al 2(SiO 3) 3 about 3.8 to 5.6 percent in United States, Canada, Brazil, Argentina, Soviet Union, Spain, and Congo. The chemical element lithium occurs in crustal rocks (18 ppm) comparable to gallium (18 ppm) and niobium (20 ppm) in the earth’s environment. Lithium was discovered by Swedish chemist Johan August Arfvedson in 1817 in the mineral petalite, the name was chosen from Greek latter lithos = stone. This fact of alkali metals developed the analytical method for precise estimation by flame photometer. All the alkali metals give characteristic flame colour due to easy excitation by electromagnetic spectrum (lithium - crimson, sodium - yellow, potassium - violet, rubidium - red-violet, cesium - blue). The large difference between the first and second ionization energy of lithium suggests that the preferred oxidation number or state of metal will be +1 and preferred to form ionic chemical bonding or compounds in chemistry. The electron configuration of the lithium atom, 1s 22s 1, the only 2s 1electron of the metal takes part in metallic bonding.
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