Two nuclei are not identical but have the same number of nucleons. These are

Options

A. isotones
B. isobars
C. isotopes
D. isodiapher

Answer

To solve the question, we need to identify the type of nuclei that are not identical but have the same number of nucleons. Here’s a step-by-step explanation:

### Step 1: Understand the Terms
- **Nucleons**: These are the particles found in the nucleus of an atom, which include protons and neutrons.
- **Mass Number (A)**: This is the total number of nucleons in a nucleus, calculated as the sum of the number of protons (Z) and the number of neutrons (N). Thus, \( A = Z + N \).
- **Atomic Number (Z)**: This is the number of protons in the nucleus of an atom, which defines the element.

### Step 2: Identify the Type of Nuclei
- The question states that the two nuclei are not identical but have the same number of nucleons. This implies that they have the same mass number (A) but different atomic numbers (Z).
- Nuclei that have the same mass number but different atomic numbers are known as **isobars**.

### Step 3: Define Isobars
- Isobars are defined as atoms of different elements that have the same mass number (A) but different atomic numbers (Z).
- For example, Carbon-14 (with 6 protons and 8 neutrons) and Nitrogen-14 (with 7 protons and 7 neutrons) are isobars because they both have a mass number of 14 but different atomic numbers.

### Step 4: Conclusion
- Therefore, the answer to the question is that the two nuclei are **isobars**.

### Final Answer
The two nuclei that are not identical but have the same number of nucleons are **isobars**.

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