Heating limestone produces

Options

A. quick lime
B. carbon dioxide
C. both (a) and (b)
D. carbon monoxide

Explanation

To solve the question "Heating limestone produces," we will follow these steps:

### Step 1: Identify the chemical composition of limestone.
Limestone is primarily composed of calcium carbonate (CaCO3).

### Step 2: Write the chemical reaction for heating limestone.
When limestone is heated, it undergoes thermal decomposition. The reaction can be written as:
\[ \text{CaCO}_3 (s) \rightarrow \text{CaO} (s) + \text{CO}_2 (g) \]
This indicates that calcium carbonate decomposes into calcium oxide (CaO) and carbon dioxide (CO2).

### Step 3: Identify the products of the reaction.
From the reaction, we can see that the products are:
1. Calcium oxide (CaO), which is also known as quicklime.
2. Carbon dioxide (CO2), which is released as a gas.

### Step 4: Analyze the options provided in the question.
The options given are:
A. Quicklime (CaO)
B. Carbon Dioxide (CO2)
C. Both A and B
D. Carbon Monoxide (CO)

From our analysis:
- Option A (Quicklime) is correct since CaO is produced.
- Option B (Carbon Dioxide) is also correct since CO2 is released.
- Option C (Both A and B) is correct as both products are formed.
- Option D (Carbon Monoxide) is incorrect as CO is not produced in this reaction.

### Step 5: Determine the correct answer.
Since both quicklime and carbon dioxide are produced, the correct answer is:
**C. Both A and B.**

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