Question

Acetic acid associates as dimers in benzene. What is the Van’t Hoff factor (i) if the degree of association of acetic acid is 50%?

• A. 0.25
• B. 0.50
• C. 0.75
  
• D. 0.40

Answer 1

The correct option is C 0.75


Given,
Degree of association $\left(\alpha \right)=50$
Number of molecules associated (n) = 2
Let the Van’t Hoff factor = i
We know that for solutes that associate in solution, $i=1+\left(\right(1/n)-1)\times \alpha$
$=1+\left(\right(1/2)–1)\times 0.5$
$=1–(0.5\times 0.5)$
$=0.75$
Therefore, the Van’t Hoff factor is equal to 0.75.