Question

The volume of a colloidal particle, $V_{c}$ as compared to volume of solute particle $V_{s}$ in a true solution could be

• A. $\frac{V_{c}}{V_{s}} \approx 10^{-3}$
• B. $\frac{V_{c}}{V_{s}} \approx 10^{3}$
• C. $\frac{V_{c}}{V_{s}} \approx 10$
• D. $\frac{V_{c}}{V_{s}} \approx 10^{22}$

Answer 1

Answer: (B)

For true solution, the diameter range is $1$ to $10 \,\mathring{A}$ and for colloidal solution, is $10$ to $1000 \,\mathring{A}$.
$\therefore \frac{V_{C}}{V_{S}}=\frac{4 / 3 \pi r_{C}^{3}}{4 / 3 \pi r_{S}^{3}}$
$=\left(\frac{r_{C}}{r_{S}}\right)^{3}=\left(\frac{10}{1}\right)^{3}=10^{3}$