For `CaCO_(3)(S) hArr CaO(s) + CO_(2) (g), Delta `H = + Q at equilibrium. The addition of more CaCO3(s) causes?

Options

A. The decrease in the concentration of CO2(g)
B. The increase in the concentration of CO2(g)
C. No change in the concentration of CO2(g)
D. Increase in the concentration of CaO(s)

Answer

To solve the question regarding the effect of adding more CaCO₃(s) on the equilibrium of the reaction:

\[ \text{CaCO}_3(s) \rightleftharpoons \text{CaO}(s) + \text{CO}_2(g) \]

with \(\Delta H = +Q\), we can follow these steps:

### Step 1: Understand the Reaction
The reaction involves the decomposition of solid calcium carbonate (CaCO₃) into solid calcium oxide (CaO) and gaseous carbon dioxide (CO₂). The reaction is at equilibrium, meaning the rates of the forward and reverse reactions are equal.

**Hint:** Identify the states of matter for each component in the reaction to understand their roles in equilibrium.

### Step 2: Apply Le Chatelier's Principle
Le Chatelier's Principle states that if a system at equilibrium is subjected to a change in concentration, temperature, or pressure, the system will adjust to counteract that change and restore a new equilibrium.

**Hint:** Recall that changes in concentration of solids do not affect the equilibrium position because their activity is constant.

### Step 3: Analyze the Addition of CaCO₃(s)
When more solid CaCO₃ is added to the system, it does not change the concentration of the gaseous product (CO₂) because solids do not affect the equilibrium concentrations. The equilibrium constant expression only includes gases and aqueous solutions.

**Hint:** Consider how the addition of a solid affects the equilibrium expression and the reaction dynamics.

### Step 4: Conclusion
Since the addition of more CaCO₃(s) does not affect the concentration of CO₂(g), there will be no change in the equilibrium position. Therefore, the concentration of CO₂ remains unchanged.

**Hint:** Look for the correct option that states there is no change in the concentration of CO₂.

### Final Answer
The addition of more CaCO₃(s) causes **no change in the concentration of CO₂(g)** at equilibrium.