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 $1000\mathring{A}$.
$\therefore \frac{V_C}{V_S}=\frac{4/3\pi r_C^3}{4/3\pi r_S^3}$
$={\left(\frac{r_C}{r_S}\right)}^3={\left(\frac{10}{1}\right)}^3=10^3$