Lithium
From Simple English Wikipedia, the free encyclopedia
Lithium (symbol Li) is the third chemical element in the periodic table, meaning that it has 3 protons in its nucleus and 3 electrons around it.
Lithium belongs to Group I. It is one of the alkali metals. Lithium is a silvery solid (when freshly cut). It is very soft. Thus it can be cut easily with a knife. It will react with water, giving off hydrogen to form an alkaline solution. Because of this, lithium must be stored in oil.
Lithium is the lightest solid element in the periodic table. It is primarily used in heat transfer alloys, in batteries and serves as a component in some drugs known as mood stabilizers.
Lithium is the lightest metal. It has a density that is only half that of water. It is very reactive. It does not occur freely in nature.
[edit] History
Lithium (Greek lithos, meaning "stone") was discovered by Johann Arfvedson in 1817.
In 1818, Christian Gmelin observed that lithium salts give a bright red color in flame.
W.T. Brande and Sir Humphrey Davy later used electrolysis on lithium oxide to isolate the element.
It was apparently given the name "lithium" because it was discovered from a mineral, while other common alkali metals were first discovered from plant tissue.
[edit] Isotopes
There are 5 isotopes of Lithium having respectively 2, 3, 4, 5 and 6 neutrons in the nucleus. The most common isotope in nature is 3Li7 which makes up 92.58 % of the total. The second isotope in abundance is 3Li6 which makes up 7.42 % of the total. The other 3 isotopes exist in very small quantities. The atomic mass of Lithium is 6.939.