Pure ozone is

Options

A. Pale blue gas
B. Dark blue liquid
C. Violet black solid
D. All the above

Answer

To determine the color of pure ozone in different states, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the States of Ozone**: Ozone can exist in three different states: gaseous, liquid, and solid.

2. **Determine the Color in Gaseous State**: In its gaseous state, pure ozone appears as a pale blue color.

3. **Determine the Color in Liquid State**: When ozone is in its liquid form, it exhibits a dark blue color.

4. **Determine the Color in Solid State**: In the solid state, ozone has a violet-black color.

5. **Summarize the Findings**:
- Gaseous state: Pale blue
- Liquid state: Dark blue
- Solid state: Violet-black

6. **Conclusion**: Therefore, the correct answer to the question "Pure ozone is" would be that it has different colors in different states, and if provided with options, the correct choice would be "all of the above".

### Final Answer:
Pure ozone is pale blue in the gaseous state, dark blue in the liquid state, and violet-black in the solid state.