Question

At STP, how many molecules of `SO_2` are in 0.400 L of `SO_2`?

Answer 1

`=0.1075*10^23` molecules of `SO_2`

Explanation:

We know1 mole or `6.022*10^23` molecules of `SO_2` occupies 22.4 L at STP
So at STP 1L will contains `6.022/22.4*10^23` molecules of `SO_2`
`:.`At STP 0.4L will contains `6.022/22.4*0.4*10^23=0.1075*10^23` molecules of `SO_2`