which of the following statements about ozone are correct ?
A. It is essential for breathing of living organisms B. It is used to disinfect water C.It absorbs ultraviolet rays D.Its proportion in air is about 3%

Options

A. A and B
B. B and C
C. A and C
D. B and D

Answer

To determine which statements about ozone are correct, let's analyze each statement one by one.

### Step 1: Analyze Statement A
**Statement A:** It is essential for breathing of living organisms.

- Ozone (O3) is not essential for breathing; in fact, it is harmful to breathe. It can damage lung tissue and cause respiratory problems. Therefore, this statement is **incorrect**.

### Step 2: Analyze Statement B
**Statement B:** It is used to disinfect water.

- Ozone is a powerful oxidizing agent. When dissolved in water, it produces a biocide that can destroy bacteria, viruses, and other microbes. This property makes ozone effective for disinfecting water. Therefore, this statement is **correct**.

### Step 3: Analyze Statement C
**Statement C:** It absorbs ultraviolet rays.

- Ozone plays a crucial role in the stratosphere by absorbing harmful ultraviolet (UV) rays from the sun. This absorption helps protect living organisms on Earth from UV radiation. Therefore, this statement is **correct**.

### Step 4: Analyze Statement D
**Statement D:** Its proportion in air is about 3%.

- The actual proportion of ozone in the atmosphere is very low, approximately 0.00006%. Hence, this statement is **incorrect**.

### Conclusion
Based on the analysis:
- Statement A: Incorrect
- Statement B: Correct
- Statement C: Correct
- Statement D: Incorrect

Thus, the correct statements about ozone are **B and C**.

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