Question

If \(A_2B \;\text{is} \;30\%\) ionised in an aqueous solution, then the value of van’t Hoff factor \( i \) is:

Hint:

The van’t Hoff factor \( i \) depends on the degree of ionisation and the number of ions produced in the solution.

Answer 1

Correct Answer: 1.6

- The van’t Hoff factor \( i \) is given by the formula: \[ i = 1 + \alpha (n-1) \] where \( \alpha \) is the degree of ionisation and \( n \) is the number of ions produced in the solution. 
- For \( \text{A}_2\text{B} \), the number of ions produced is 3 (two A+ ions and one B- ion). 
- Given that the compound is 30% ionised, \( \alpha = 0.30 \). 
Thus, \( i = 1 + 0.30(3-1) = 1.60 \).