Which of the following is not a correct statement ?

Options

A. Transparent soap are made by dissolving the soap in ethanol and then evaporating excess solvent.
B. Soaps that float in water are made by beating tiny air bubbles before their hardening .
C. Medicated soaps contian alcohol to prevent rapid drying .
D. Potassium soaps are soft to the skin than sodium soaps.

Explanation

To determine which statement is not correct, let's analyze each option step by step.

### Step 1: Analyze the first statement
**Statement:** Transparent soaps are made by dissolving the soap in ethanol and then evaporating the excess solvent.
**Analysis:** This statement is correct. Transparent soaps are indeed produced by dissolving soap in ethanol, which acts as a solvent. After the soap is dissolved, the excess ethanol is evaporated, resulting in a clear soap.

### Step 2: Analyze the second statement
**Statement:** Soaps that float in water are made by beating tiny air bubbles before they are hardened.
**Analysis:** This statement is also correct. The process of incorporating air bubbles into the soap mixture allows the soap to float on water. This is a common method used in the production of floating soaps.

### Step 3: Analyze the third statement
**Statement:** Medicated soaps contain alcohol to prevent rapid drying.
**Analysis:** This statement is incorrect. Alcohol is a volatile substance that tends to evaporate quickly, which can lead to drying rather than preventing it. Medicated soaps often contain ingredients like glycerol to retain moisture, not alcohol.

### Step 4: Analyze the fourth statement
**Statement:** Potassium soaps are softer on the skin than sodium soaps.
**Analysis:** This statement is correct. Potassium soaps are generally milder and softer on the skin compared to sodium soaps, which are often used in laundry applications and can be harsher.

### Conclusion
The statement that is not correct is: **"Medicated soaps contain alcohol to prevent rapid drying."** This is the answer to the question.