In an equilibrium reaction for which `DeltaG^(ɵ)=0`, the equilibrium constant `K` should be equal to :

Options

A. Zero
B. `10`
C. `1`
D. `2`

Explanation

To solve the question regarding the equilibrium constant \( K \) when \( \Delta G^{\circ} = 0 \), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Relationship**: The relationship between the standard Gibbs free energy change (\( \Delta G^{\circ} \)) and the equilibrium constant (\( K \)) is given by the equation:
\[ \Delta G^{\circ} = -2.303RT \log K \]
where \( R \) is the universal gas constant and \( T \) is the temperature in Kelvin.

2. **Substitute \( \Delta G^{\circ} = 0 \)**: Since we are given that \( \Delta G^{\circ} = 0 \), we can substitute this value into the equation:
\[ 0 = -2.303RT \log K \]

3. **Analyze the Equation**: The equation simplifies to:
\[ -2.303RT \log K = 0 \]
Since \( -2.303RT \) is not equal to zero (as \( R \) and \( T \) are positive constants), we can conclude that:
\[ \log K = 0 \]

4. **Find \( K \)**: The next step is to solve for \( K \) using the property of logarithms. If \( \log K = 0 \), then:
\[ K = 10^0 \]
Therefore:
\[ K = 1 \]

5. **Conclusion**: The equilibrium constant \( K \) when \( \Delta G^{\circ} = 0 \) is equal to 1.

### Final Answer:
The equilibrium constant \( K \) should be equal to **1**.

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