Which is the incorrect statement

Options

A. Emulsions of oil in water are unstable
B. Emulsifying agent stavilises an emulsion
C. For stabilisation of W/O emulsion soap is used
D. The droplets in emulsions can be precipitated
by electrolytes

Answer

To determine which statement is incorrect regarding emulsions, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Emulsion of oil in water are unstable.**
- Emulsions can be either stable or unstable. Oil-in-water emulsions can be stable if properly formulated, but they can also break down over time due to the coalescence of droplets. Hence, this statement is generally considered **correct** as it acknowledges the potential instability of emulsions.

**Hint:** Consider the nature of emulsions and the factors affecting their stability.

2. **Statement 2: Emulsifying agent stabilizes an emulsion.**
- Emulsifying agents, also known as surfactants, are indeed used to stabilize emulsions by reducing the surface tension between the two immiscible liquids (oil and water). This statement is **true**.

**Hint:** Think about the role of surfactants in reducing surface tension.

3. **Statement 3: For stabilization of water-oil emulsion, soap is used.**
- While soap can be used as an emulsifying agent, it is not the only or the most effective agent for stabilizing water-oil emulsions. There are many other emulsifiers that are more effective than soap. Thus, this statement can be considered **incorrect** in the context that it implies soap is the primary or only emulsifying agent used.

**Hint:** Reflect on the variety of emulsifying agents available and their effectiveness.

4. **Statement 4: The droplet in emulsion can be precipitated by electrolytes.**
- This statement is correct. The droplets in an emulsion can carry a charge, and the addition of electrolytes can neutralize this charge, leading to coalescence and precipitation. Thus, this statement is **true**.

**Hint:** Consider how electrolytes interact with charged particles in an emulsion.

### Conclusion:
The incorrect statement among the options provided is **Statement 3: For stabilization of water-oil emulsion, soap is used.**