Dissolution of sodium sulphate in water is exothermic (with evolution of heat). If the temperature is raised for a saturated solution of sodium sulphate , then according to Le - Chatelier principle

Options

A. The solution will become supersaturated
B. Some solid will precipitate out from the solution
C. More solid will dissolve
D. Solution connectration will remain unchanged

Answer

To solve the question regarding the dissolution of sodium sulfate in water and its relation to Le Chatelier's principle, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process**:
- The dissolution of sodium sulfate (Na2SO4) in water is an exothermic process, meaning it releases heat. This can be represented as:
\[ \text{Na}_2\text{SO}_4 (s) + \text{H}_2\text{O} (l) \rightarrow \text{Na}_2\text{SO}_4 (aq) + \text{heat} \]

2. **Defining Saturated Solution**:
- A saturated solution is one in which no more solute can dissolve at a given temperature. The system is at equilibrium, meaning the rate of dissolution equals the rate of crystallization.

3. **Applying Le Chatelier's Principle**:
- According to Le Chatelier's principle, if a system at equilibrium is subjected to a change in temperature, pressure, or concentration, the system will adjust to counteract that change and restore a new equilibrium.

4. **Effect of Increasing Temperature**:
- Since the dissolution of sodium sulfate is exothermic, increasing the temperature will shift the equilibrium to favor the endothermic direction (which is the reverse reaction in this case). This means that the system will try to absorb the added heat by favoring the formation of solid sodium sulfate (Na2SO4) from the aqueous solution.

5. **Conclusion**:
- As a result of increasing the temperature for a saturated solution of sodium sulfate, some of the dissolved sodium sulfate will precipitate out of the solution, leading to the formation of a supersaturated solution. This means that the equilibrium shifts to the left, resulting in the crystallization of solid Na2SO4.

### Final Answer:
The correct conclusion is that upon increasing the temperature of a saturated solution of sodium sulfate, some solid will precipitate out from the solution due to the backward reaction, leading to a supersaturated solution.

---