Which of the following favours the reverse reaction in chemical equilibrium ?

Options

A. Increasing the concentration of the reactant
B. Removal of at least one of the products at regular intervals
C. Increasing the concentrations of one or more of the products
D. increasing the pressure.

Explanation

To determine which conditions favor the reverse reaction in a chemical equilibrium, we can apply Le Chatelier's principle. Let's analyze the situation step by step.

### Step-by-Step Solution:

1. **Understanding the Reaction**:
- Consider a reversible reaction:
\[ A + B \rightleftharpoons C + D \]
- In this reaction, \(A\) and \(B\) are the reactants, while \(C\) and \(D\) are the products.

2. **Le Chatelier's Principle**:
- This principle states that if an external change is applied to a system at equilibrium, the system will adjust itself to counteract that change and restore a new equilibrium.

3. **Increasing Concentration of Products**:
- If we increase the concentration of products \(C\) and \(D\), the system will respond by favoring the reverse reaction to reduce the concentration of these products.
- Therefore, increasing the concentration of one or more of the products will shift the equilibrium to the left (toward the reactants).

4. **Analyzing the Options**:
- **Option A**: Increasing the concentration of reactants \(A\) and \(B\) will favor the forward reaction, not the reverse.
- **Option B**: Removing one or more products will also favor the forward reaction, as it reduces the concentration of products.
- **Option C**: Increasing the concentration of one or more products \(C\) or \(D\) will favor the reverse reaction. This is the correct answer.
- **Option D**: Increasing the pressure affects the reaction direction depending on the number of gaseous moles involved, and cannot be generalized to favor the reverse reaction.

5. **Conclusion**:
- The condition that favors the reverse reaction is **Option C**: Increasing the concentration of one or more of the products.

### Final Answer:
**Option C**: Increasing the concentration of one or more of the products.