Which is used in purification of air in the space craft.

Options

A. Slaked lime
B. Quick lime
C. Pottassium superoxide
D. `CaCl_(2)`

Answer

To solve the question "Which is used in purification of air in the spacecraft?" we will analyze the given options and identify the correct one.

### Step 1: Identify the compounds
We have the following options:
1. Slaked lime (Ca(OH)₂)
2. Quick lime (CaO)
3. Potassium superoxide (KO₂)
4. Calcium chloride (CaCl₂)

### Step 2: Understand the function of each compound
- **Slaked lime (Ca(OH)₂)**: This is primarily used in construction and as a pH regulator, but it is not known for air purification.
- **Quick lime (CaO)**: This compound is used in various industrial processes, but it does not serve as an air purifier.
- **Potassium superoxide (KO₂)**: This compound is known for its ability to absorb carbon dioxide and release oxygen, making it useful for air purification in closed environments like spacecraft.
- **Calcium chloride (CaCl₂)**: This is commonly used as a desiccant and for de-icing, but it does not purify air.

### Step 3: Determine the correct answer
From the analysis, we find that potassium superoxide (KO₂) is specifically used for air purification in spacecraft due to its ability to absorb CO₂ and release O₂.

### Conclusion
The correct answer is **Potassium superoxide (KO₂)**.

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