`CNS^(ө)` ions give red colour with `Fe^(3+)` ions in aqueous solution as:
`Fe^(3+)(aq) + 3CNS^(ө)(aq) rarr Feunderset("red")((CNS))_(3)(aq) `
If `0.1 M` `KCNS` solution is separated from `0.1 M FeCl_(3)` solution by means of a semi-permeable membrane, red colour will appear on:
a.`FeCl_(3)` soluion , b. `KCNS` solution side ,
c. Both sides , d. Neither side

Explanation

To solve the problem, we need to analyze the situation where a 0.1 M KCNS solution is separated from a 0.1 M FeCl₃ solution by a semi-permeable membrane. We are interested in determining where the red color will appear due to the formation of the Fe(CNS)₃ complex.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
The reaction between Fe³⁺ ions and CNS⁻ ions is given by:
\[
\text{Fe}^{3+}(aq) + 3 \text{CNS}^-(aq) \rightarrow \text{Fe(CNS)}_3(aq) \quad \text{(red color)}
...