500mL of `NH_(3)` contains `6.02xx10^(23)` molecules at STP. How many molecules are present in 100 mL of `CO_(2)` at STP?

Options

A. `6 xx 10^(23)`
B. `1.5 xx 10^(23)`
C. `1.2 xx 10^(23)`
D. None of these

Answer

C

Explanation

`(PV_(1))/(n_(2)RT)=(PV_(2))/(n_(2)RT)` or , `(V_(1))/(n_(1))=(V_(2))/(n_(2))`
or , `(500)/(1)=(100)/(n_(2))` or , `n_(2)=(1)/(5)`
`[6.0 xx 10^(23)` molecules of `NH_(3)=1` mole ]
1 mole of `CO_(2)` contains `6.0 xx 10^(23)` molecules
`:. (1)/(5)` mole of `CO_(2)` contains `1.2 xx 10^(23)` molecules