Schiff's reagent is `:`

Options

A. Magenta colour solution decolourised with sulphurous acid
B. Ammonical cobalt chloride solution
C. Ammonical manganese sulphate solution
D. Magenta solution decolourised with chlorine

Answer

### Step-by-Step Text Solution:

**Step 1: Definition of Schiff's Reagent**
Schiff's reagent is a chemical reagent used primarily for the detection of aldehydes. It is an aqueous solution of rosaniline hydrochloride, which appears as a magenta or pink-colored solution.

**Step 2: Preparation of Schiff's Reagent**
To prepare Schiff's reagent, rosaniline hydrochloride is treated with sulfur dioxide (SO2). This treatment decolorizes the pink solution, resulting in a colorless solution.

**Step 3: Detection of Aldehydes**
When an aldehyde is introduced to the colorless Schiff's reagent, it reacts with the aldehyde and the solution is restored to its original pink color. This color change indicates the presence of aldehydes in the sample.

**Step 4: Summary of Characteristics**
- Schiff's reagent is a magenta-colored solution of rosaniline hydrochloride.
- It is used to detect the presence of aldehydes.
- The reagent is decolorized by sulfur dioxide and restored to pink by aldehydes.