Number of atoms of oxygen present in 10.6 g of `Na_(2)CO_(3)` will be

Options

A. `6.02xx10^(22)`
B. `12.04xx10^(22)`
C. `1.806xx10^(23)`
D. `31.80xx10^(28)`

Answer

C

Explanation

Molar mass of `Na_(2)CO_(3) = 2xx23+1216xx3`
`=46+12+48`
`=106gmol^(-1)`
`:.` 10.6 g of `Na_(2)CO_(3)-=0.1` mol of `Na_(2)CO_(3)`
`=0.3` mol of oxygen atoms
`=0.3xx6.02xx10^(-23)` oxygen atom
`=1.806xx10^(23)` oxygen atom