Inorganic catalysts are

Options

A. Usually small and simple molecules
B. Not specific for any one reaction
C. Not present in living cells
D. All of these

Answer

**Step-by-Step Text Solution:**

1. **Understanding Inorganic Catalysts**: Inorganic catalysts are substances that can alter the rate of chemical reactions without being consumed in the process. They are typically small and simple molecules.

2. **Characteristics of Inorganic Catalysts**:
- **Not Specific**: Unlike enzymes (which are organic catalysts), inorganic catalysts are not specific to a single reaction. They can facilitate multiple types of reactions.
- **Presence in Living Cells**: Inorganic catalysts are generally not found in living cells, which primarily utilize organic catalysts (enzymes) for biochemical reactions.

3. **Examples of Inorganic Catalysts**: Common examples include metal oxides like vanadium oxide and titanium chloride, as well as substances like hydrogen peroxide (H2O2), which can decompose into water and oxygen gas.

4. **Conclusion**: Based on the characteristics and examples provided, we can conclude that all the statements regarding inorganic catalysts are correct. Therefore, the answer to the question is that inorganic catalysts are usually small and simple molecules, not specific for any one reaction, and not present in living cells.

**Final Answer**: All of the above statements are correct for inorganic catalysts.

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