The increase of pressure on ice water system at constant temperature will lead to :

Options

A. a shift of the equilibrium in the forward direction
B. a decrease in the entropy of the system
C. an increase in the Gibbs energy of the systed no effect on the equilibrium
D. no effect on the equilibrium

Answer

To solve the question regarding the effect of increased pressure on the ice-water system at constant temperature, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the System**: The system consists of ice and water in equilibrium. The equilibrium reaction can be represented as:
\[ \text{Ice (s)} \rightleftharpoons \text{Water (l)} \]

2. **Effect of Pressure on Equilibrium**: According to Le Chatelier's principle, if a system at equilibrium is subjected to a change in pressure, the equilibrium will shift in the direction that reduces the pressure.

3. **Density Consideration**: Ice has a lower density than water. This means that when we apply pressure, we are effectively favoring the phase that occupies less volume.

4. **Volume and Density Relationship**: When pressure increases, the volume of the system decreases (since pressure and volume are inversely related). Since the mass remains constant, if the volume decreases, the density must increase.

5. **Direction of Shift**: Since water is denser than ice, increasing the pressure will favor the formation of water from ice. Thus, the equilibrium will shift to the right (forward direction).

6. **Conclusion**: Therefore, the increase of pressure on the ice-water system at constant temperature will lead to a shift in equilibrium towards the formation of water, which is the forward direction of the reaction.

### Final Answer:
The increase of pressure on the ice-water system at constant temperature will lead to a shift in equilibrium towards the formation of water (forward direction).

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