A radioactive ncleus A finaly transforms into a stable nucleus. B Then A and B can be

Options

A. isobars
B. isotones
C. isotopes
D. None of these

Answer

To solve the question regarding the transformation of a radioactive nucleus A into a stable nucleus B, we need to analyze the definitions of isobars, isotopes, and isotones, and how they relate to the transformation process.

### Step-by-Step Solution:

1. **Understanding the Terms**:
- **Isotope**: Nuclei that have the same number of protons but different numbers of neutrons.
- **Isobar**: Nuclei that have the same mass number (total number of protons and neutrons) but different numbers of protons and neutrons.
- **Isotone**: Nuclei that have the same number of neutrons but different numbers of protons.

2. **Analyzing the Transformation**:
- A radioactive nucleus A is unstable and transforms into a stable nucleus B.
- During this transformation, the nucleus A undergoes decay, which typically involves the emission of particles (like alpha or beta particles) that change the number of protons and/or neutrons.

3. **Determining the Relationship**:
- Since nucleus A is unstable and transforms into a stable nucleus B, the number of protons in nucleus A may change during the decay process.
- If the number of protons changes, then the number of neutrons must also change to maintain stability, leading to the formation of a new isotope.

4. **Evaluating the Options**:
- **Option A (Isobars)**: This cannot be correct because isobars have the same mass number but different proton counts, which does not guarantee stability.
- **Option B (Isotones)**: This cannot be correct either, as isotones have the same number of neutrons but different protons, which does not apply to the transformation from an unstable to a stable nucleus.
- **Option C (Isotopes)**: This is the correct option because the transformation involves a change in the number of neutrons, resulting in a different isotope of the element.
- **Option D (None of these)**: This option is incorrect as we have identified that A and B are isotopes.

5. **Conclusion**:
- Therefore, when a radioactive nucleus A finally transforms into a stable nucleus B, A and B can be classified as isotopes.

### Final Answer:
A and B can be isotopes.

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