Which of the following statement is not true regarding acids ?

Options

A. They have a sour taste.
B. They are good conductors of electricity
C. They turn red litmus to blue.
D. They are corrosive in nature.

Explanation

To solve the question "Which of the following statement is not true regarding acids?", we will analyze each statement provided and determine which one is incorrect.

### Step-by-Step Solution:

1. **Understanding Acids**:
- Acids are substances that can release hydrogen ions (H⁺) when dissolved in water. This is the fundamental property of acids.

2. **Analyzing the Statements**:
- **Statement 1**: "Acids have a sour taste."
- This statement is true. Many acids, such as citric acid in lemons and acetic acid in vinegar, are known for their sour taste.

- **Statement 2**: "Acids are good conductors of electricity."
- This statement is also true. Acids dissociate into ions in solution, which allows them to conduct electricity effectively.

- **Statement 3**: "Acids turn red litmus paper to blue."
- This statement is false. Acids actually turn blue litmus paper red. The litmus test indicates whether a solution is acidic or basic; red litmus paper turns blue in basic solutions, while blue litmus paper turns red in acidic solutions.

- **Statement 4**: "Acids are corrosive in nature."
- This statement is true. Many acids, such as sulfuric acid and hydrochloric acid, can cause corrosion and damage to materials, including skin.

3. **Identifying the Incorrect Statement**:
- From the analysis, we see that Statement 3 is not true regarding acids. Therefore, the answer to the question is that Statement 3 is the one that is incorrect.

### Final Answer:
The statement that is not true regarding acids is: **"Acids turn red litmus paper to blue."**