Question

The weight of one molecule of a compound $C _{60} H _{122}$ is

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

Answer 1

Answer: (C)

Molecular weight of $C _{60} H _{122}=60 \times 12+1 \times 122=842$

$\therefore $ Weight of $1 mole$ of $C _{60} H _{122}$ molecules $=842\, g$

$\Rightarrow $ Weight of $6.023 \times 10^{23}$ molecules $=842\, g$

$\Rightarrow $ Weight of 1 molecule $=\frac{842}{6.023 \times 10^{23}}=1.4 \times 10^{-21} \,g$