Question

The value of van't Hoff factor, i, for CH₃COOH solution in water will be

• A. Between 1 and 2
• B. Less than 1
• C. 2
• D. 1

Hint:

For weak electrolytes like acetic acid, the van't Hoff factor is always between 1 and 2, depending on the degree of dissociation.

Answer 1

The Correct Option is A

Step 1: Understanding van't Hoff factor.
The van't Hoff factor (i) quantifies the number of particles a solute forms upon dissolution in a solvent. For non-electrolytes, i is 1. For electrolytes, i varies with the degree of dissociation.
Step 2: Behavior of acetic acid in water.
Acetic acid (CH₃COOH), a weak electrolyte, dissociates partially in water according to the equilibrium:\[\text{CH₃COOH} \rightleftharpoons \text{CH₃COO}⁻ + \text{H}⁺\]Consequently, it does not dissociate completely into ions, resulting in a van't Hoff factor (i) greater than 1 but less than 2.
Step 3: Conclusion.
The van't Hoff factor for a CH₃COOH solution in water falls between 1 and 2 due to its partial ionic dissociation.
Final Answer: \[\boxed{\text{The van't Hoff factor is between 1 and 2}}\]