Assertion : 1 amu equals to `1.66xx10^(-24)` g.
Reason : `1.66xx10^(-24)g` equals to `1/12` th of mass of a `C^(12)` atom.

Options

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

Explanation

To analyze the assertion and reason provided in the question, we will break down the concepts step by step.

### Step 1: Understanding the Assertion
The assertion states that 1 atomic mass unit (amu) is equal to \(1.66 \times 10^{-24}\) grams.

**Explanation**:
- The atomic mass unit (amu) is a standard unit of mass that quantifies mass on an atomic or molecular scale.
- It is defined as one twelfth (1/12) of the mass of a carbon-12 (\(C^{12}\)) atom.

### Step 2: Verifying the Assertion
To verify the assertion, we can refer to the known value of 1 amu, which is approximately \(1.66 \times 10^{-24}\) grams.

**Conclusion**:
- The assertion is correct as it matches the accepted scientific value.

### Step 3: Understanding the Reason
The reason states that \(1.66 \times 10^{-24}\) grams is equal to \(1/12\) of the mass of a \(C^{12}\) atom.

**Explanation**:
- The mass of a carbon-12 atom is defined as exactly 12 amu. Therefore, \(1\) amu is indeed \(1/12\) of the mass of a carbon-12 atom.
- This relationship is fundamental in defining the atomic mass unit.

### Step 4: Verifying the Reason
To verify the reason, we can recall the definition of the atomic mass unit:
- Since 1 amu is defined as \(1/12\) of the mass of a \(C^{12}\) atom, the reason is also correct.

### Final Conclusion
Both the assertion and the reason are correct. The reason correctly explains why the assertion holds true.

### Summary
- Assertion: 1 amu = \(1.66 \times 10^{-24}\) g (Correct)
- Reason: \(1.66 \times 10^{-24}\) g = \(1/12\) of the mass of a \(C^{12}\) atom (Correct)
- Both are correct and the reason provides a valid explanation for the assertion.

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