Actication energy is always lowered by positive catalyst. T or F

Answer

To determine whether the statement "Activation energy is always lowered by positive catalyst" is true or false, we can analyze the role of catalysts in chemical reactions step by step.

### Step-by-Step Solution:

1. **Understanding Catalysts**:
- Catalysts are substances that alter the rate of a chemical reaction without being consumed in the process. They can be classified as positive (or accelerating) catalysts and negative (or inhibiting) catalysts.

2. **Role of Positive Catalysts**:
- A positive catalyst increases the rate of a reaction. It does this by providing an alternative reaction pathway that has a lower activation energy (Ea).

3. **Activation Energy (Ea)**:
- Activation energy is the minimum energy required for a reaction to occur. It is a barrier that reactants must overcome to be converted into products.

4. **Effect of Positive Catalysts on Activation Energy**:
- When a positive catalyst is present, it lowers the activation energy required for the reaction. This means that more molecules have the necessary energy to react, which increases the reaction rate.

5. **Mathematical Representation**:
- The relationship between the rate constant (k), activation energy (Ea), and temperature (T) can be expressed using the Arrhenius equation:
\[ k = A e^{-\frac{E_a}{RT}} \]
- In this equation, A is the pre-exponential factor, R is the gas constant, and T is the temperature. If Ea decreases (due to the presence of a positive catalyst), the exponential term increases, leading to a higher rate constant (k) and thus a faster reaction rate.

6. **Conclusion**:
- Since a positive catalyst always lowers the activation energy, the statement "Activation energy is always lowered by positive catalyst" is **True**.

### Final Answer:
**True**. Activation energy is always lowered by a positive catalyst.