The decreasing order of value of van't Hoff factor for the following in aqueous medium is
(A) $K_3[Fe(CN)_6]$
(B) $NaCl$
(C) $K_2SO_4$
(D) $C_6H_{12}O_6$
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (A), (C), (B), (D)
1. (A) $K_3[Fe(CN)_6]$ (Potassium ferricyanide)
This is a complex salt that dissociates into three potassium ions and one complex ferricyanide ion:
$K_3[Fe(CN)_6] \rightarrow 3K^+ + [Fe(CN)_6]^{3-}$
- Total particles ($i$): $3 + 1 = \mathbf{4}$
2. (C) $K_2SO_4$ (Potassium sulfate)
This salt dissociates into two potassium ions and one sulfate ion:
$K_2SO_4 \rightarrow 2K^+ + SO_4^{2-}$
- Total particles ($i$): $2 + 1 = \mathbf{3}$
3. (B) $NaCl$ (Sodium chloride)
This salt dissociates into one sodium ion and one chloride ion:
$NaCl \rightarrow Na^+ + Cl^-$
- Total particles ($i$): $1 + 1 = \mathbf{2}$
4. (D) $C_6H_{12}O_6$ (Glucose)
Glucose is a non-electrolyte. It dissolves in water but does not dissociate into ions.
- Total particles ($i$): $\mathbf{1}$
Final Decreasing Order
Comparing the values:
$4 \text{ (A)} > 3 \text{ (C)} > 2 \text{ (B)} > 1 \text{ (D)}$