Question

Volume occupied by one molecule of water (density = $1\, g\, cm ^{-3}$ ) is

• A. $5.5 \times 10^{-23} cm ^{3}$
• B. $9.0 \times 10^{-23} cm ^{3}$
• C. $6.023 \times 10^{-23} cm ^{3}$
• D. $3.0 \times 10^{-23} cm ^{3}$

Answer 1

Answer: (D)

As water is liquid its density $=1\, g / mL$
i.e., $1\, g$ of $H _{2} O$ have volume $=1\, mL$
Mass of one molecule $=\frac{18}{6.023 \times 10^{23}} g$
$\therefore \frac{18}{6.023 \times 10^{23}} g$ of $H _{2} O$ have volume
$=\frac{18}{6.022 \times 10^{23}} mL =3.0 \times 10^{-23} mL$