How many atoms are there in 10.2 l of ar gas at stp?

3.011×0²³  atoms of Ar

Explanation:

To find no.of atoms of Ar gas in 10.2 L at STP.

At STP 1 mole of a gas occupies 22.4  L  and contains 6.022×10²³ atoms/molecules or ions.

At STP

22.4 L contains 1 mole Ar t

10.2 L contains (10.2÷22.4)×1 Ar

mole Ar contains ×6.022×10²³

=3.011×0²³  atoms of Ar

the answer is c.the valence of the atoms combine .