Question

The weight of one molecule of a compound of molecular formula $C_{60}{H}_{122}$ is:

• A. $1.2\times {10}^{-20}g$
• B. $5.025\times {10}^{-23}g$
• C. $1.4\times {10}^{-21}g$
• D. $6.023\times {10}^{-20}g$

Answer 1

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

Weight of 1 mole of $C_{60}{H}_{122}=M.W.=60\times 12+122\times 1=842$

Number of molecules in 1 mole $C_{60}{H}_{122}=6.023\times {10}^{23}$

Weight of one molecule $=\frac{842}{6.02\times {10}^{23}}gm$

$=140\times {10}^{-23}g=1.4\times {10}^{-21}g$.

Hence, the correct option is $\text{C}$