Question

The volume occupied by one molecule of water at $4^{o}C$ is:

• A. $3\times {10}^{-23}cc$
• B. $3\times {10}^{23}cc$
• C. $3\times {10}^{-24}cc$
• D. $3\times {10}^{24}cc$

Answer 1

The correct option is A $3\times {10}^{-23}cc$

The molar volume, symbol $V_m$, is the volume occupied by one mole of a substance (chemical element or chemical compound) at a given temperature and pressure. It is equal to the molar mass (M) divided by the mass density (ρ). It has the SI unit cubic metres per mole $\left(\frac{m^3}{mol}\right)$.

$N_A$ $=$ $6.022\times {10}^{23}$

molecular mass of water $=$ 18 gm

therefore,1 molecule $=$ $\frac{18}{6.022\times {10}^{23}}$

$=$ $3.0\times {10}^{-23}gm$

we know,

Density $=$ $\frac{mass}{volume}$

Volume $=$ $\frac{3.0\times {10}^{-23}gm}{1gm}$

$=$ $3.0\times {10}^{-23}c{m}^3$