Question

The rates of diffusion of $SO _{2}, CO _{2}, PCl _{3}$ and $SO _{3}$ are in the following order

• A. $CO _{2}> SO _{2}> PCl _{3}> SO _{3}$
• B. $PCl _{3}> SO _{3}> SO _{2}> CO _{2}$
• C. $SO _{2}> SO _{3}> PCl _{3}> CO _{2}$
• D. $CO _{2}> SO >2> SO _{3}> PCl _{3}$

Answer 1

Answer: (D)

Rate of diffusion is the change in number of diffusing molecules inside the cell over a time.
Since, net movement of diffusion depends on the concentration gradient, the rate of diffusion $\propto$ concentration gradient across the membrane.
Also, the ratio of rate of diffusion is inversely proportional to the square root of the masses.
$\because$ Mass of $SO _{2}=64$
Mass of $CO _{2}=44$
Mass of $SO _{3}=80$
Mass of $PCl _{3}=137$
$\therefore $ Rate of diffusion of $SO _{2}, CO _{2}, PCl _{3}$ and $SO _{3}$, is
$CO _{2}> SO _{2}> SO _{3}> PCl _{3}$