Question

What is the mass of $1$ molecule of $CO$.

• A. $2.325\times 10^{-23}$
• B. $4.65\times 10^{-23}$
• C. $3.732\times 10^{-23}$
• D. $2.895\times 10^{-23}$

Answer 1

Answer: (B)

Gram molecular weight of $CO=12+16=28g$
$6.023\times 10^{23}$ molecules of $CO$ weigh $28g$
$1$ molecule of $CO$ weigh $=\frac{28}{6.02\times 10^{23}}=4.65\times 10^{-23}g$