Question

The mass of a molecule of the compound $C_{60}{H}_{122}$ is __________.

• A. $1.4\times {10}^{-21}$ g
• B. $1.09\times {10}^{-21}$ g
• C. $5.025\times {10}^{23}$ g
• D. $16.023\times {10}^{23}$ g

Answer 1

The correct option is A $1.4\times {10}^{-21}$ g

Molecular mass of $C_{60}{H}_{122}=(60\times 12+1\times 122)=720+122=842$

Hence, one mole contains $6.022\times {10}^{23}$ molecules

Therefore,

Mass of one molecule $=\frac{842}{6.022\times {10}^{23}}$

$=1.4\times {10}^{-21}g$

The correct option is A.