Question

chemical formulae of elements and their uses

Answer 1

aluminium is used in vehicle ,plane construction.
argon it is useful in fluorescent lighting tubes. 
boron is used for fiberglass,polymers,ceramics.

Answer 2

Some of the chemical formula of elements are :
Ammonia - NH3
Aluminium. - Al
Barium. - Ba
Beryllium. - Be
Boron. - B
Carbon. - C
Calcium. - Ca
Copper. - Cu
Gallium. - Ga
Gold. - Au
Germanium. - Ge
Hydrogen. - H
Helium. - He
Iron - Fe
Lithium. - Li
Magnesium. - Mg
Manganese. - Mn
Nitrogen - N
Neon. - Ne
Oxygen - O
Potassium. - K
Silver. - Ag
Tin. - Sn
There are lots of elements the listed above are some of them
I hope it helps you
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