Which of the following statements is true?

Options

A. `DeltaG` is always less than `DeltaH`
B. `DeltaG` is always more than `DeltaH`
C. `DeltaG` is always proportional to `DeltaH`
D. `DeltaG` may be lesser, greater or equal to `DeltaH`

Explanation

To determine which of the statements regarding the relationship between ΔG (Gibbs free energy change) and ΔH (enthalpy change) is true, we can analyze the equation that relates these two thermodynamic quantities:

### Step-by-Step Solution:

1. **Understand the Equation**: The relationship between ΔG and ΔH is given by the equation:
\[ \Delta G = \Delta H - T \Delta S \]
where ΔS is the change in entropy and T is the temperature in Kelvin.

2. **Analyze the Terms**: From the equation, we can see that ΔG depends on both ΔH and the term \(T \Delta S\). This means that the value of ΔG can vary based on the values of ΔH, T, and ΔS.

3. **Consider Different Scenarios**:
- If \(T \Delta S\) is positive and large enough, then ΔG can be less than ΔH (ΔG < ΔH).
- If \(T \Delta S\) is negative, then ΔG can be greater than ΔH (ΔG > ΔH).
- If \(T \Delta S\) is zero (which can occur at absolute zero temperature or if ΔS is zero), then ΔG equals ΔH (ΔG = ΔH).

4. **Conclusion**: Since ΔG can be less than, greater than, or equal to ΔH depending on the values of T and ΔS, the correct statement is:
\[ \Delta G \text{ may be lesser, greater, or equal to } \Delta H. \]

### Final Answer:
The true statement is: **ΔG may be lesser, greater, or equal to ΔH.**