Assertion. Both 106 g of sodium carbonate and 12 g of carbon have same number of carbon atoms.
Reason. Both contain 1 g atom of carbon which contains `6.023xx10^(23)` carbon atoms.

Options

A. If both assertion and reason are true, and reason is the true explanation of the assertion.
B. If both assertion and reason are true, but reason is not the true explanation of the assetion.
C. If assertion is true, but reason if false
D. If both assertion and reason are false.

Explanation

To solve the question, we need to evaluate both the assertion and the reason provided.

### Step 1: Analyze the Assertion
The assertion states that both 106 g of sodium carbonate (Na2CO3) and 12 g of carbon have the same number of carbon atoms.

1. **Determine the Molar Mass of Sodium Carbonate (Na2CO3)**:
- Sodium (Na) has a molar mass of approximately 23 g/mol.
- Carbon (C) has a molar mass of approximately 12 g/mol.
- Oxygen (O) has a molar mass of approximately 16 g/mol.
- Molar mass of Na2CO3 = (2 × 23) + (1 × 12) + (3 × 16) = 46 + 12 + 48 = 106 g/mol.

2. **Calculate the Number of Moles in 106 g of Na2CO3**:
- Moles of Na2CO3 = mass (g) / molar mass (g/mol) = 106 g / 106 g/mol = 1 mole.

3. **Determine the Number of Carbon Atoms in 1 Mole of Na2CO3**:
- Each molecule of Na2CO3 contains 1 carbon atom.
- Therefore, 1 mole of Na2CO3 contains 1 mole of carbon atoms.

4. **Calculate the Number of Carbon Atoms**:
- Using Avogadro's number (6.022 × 10^23), the number of carbon atoms in 1 mole is 6.022 × 10^23 atoms.

### Step 2: Analyze the Reason
The reason states that both substances contain 1 gram atom of carbon, which corresponds to 6.023 × 10^23 carbon atoms.

1. **Determine the Number of Moles in 12 g of Carbon**:
- Moles of Carbon = mass (g) / molar mass (g/mol) = 12 g / 12 g/mol = 1 mole.

2. **Calculate the Number of Carbon Atoms in 1 Mole of Carbon**:
- Similar to Na2CO3, 1 mole of carbon also contains 6.022 × 10^23 carbon atoms.

### Conclusion
Both 106 g of sodium carbonate and 12 g of carbon contain the same number of carbon atoms (6.022 × 10^23). Therefore, the assertion is true.

The reason is also true because both substances contain 1 mole of carbon, which corresponds to 6.022 × 10^23 carbon atoms.

### Final Answer
Both the assertion and the reason are true, and the reason correctly explains the assertion.

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