how would you describe its physical appearance?
Lithium has a single valence electron that is easily given up to form a cation.
Lithium
lithium has a single valence electron that is easily given up to form a cation. 
where can lithium be found in the world UNANSWERABLE what is the atomic number of this element? Atomic number 3
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Lithium [SEP] Atomic and physical
Like the other alkali metals, lithium has a single valence electron that is easily given up to form a cation. Because of this, lithium is a good conductor of heat and electricity as well as a highly reactive element, though it is the least reactive of the alkali metals. Lithium's low reactivity is due to the proximity of its valence electron to its nucleus (the remaining two electrons are in the 1s orbital, much lower in energy, and do not participate in chemical bonds). However, molten lithium is significantly more reactive than its solid form. Lithium metal is soft enough to be cut with a knife.