Atoms with the same mass number but having different nuclear charges are called

Options

A. Isotopes
B. Isobars
C. Isohores
D. Isotones

Explanation

To solve the question "Atoms with the same mass number but having different nuclear charges are called," we can follow these steps:

### Step 1: Understand the Terms
- **Mass Number**: The total number of protons and neutrons in an atom's nucleus.
- **Nuclear Charge**: The total charge of the nucleus, which is determined by the number of protons (atomic number).

### Step 2: Identify the Key Concept
We need to identify the type of atoms that have the same mass number but different nuclear charges.

### Step 3: Define Isobars
Atoms that have the same mass number but different atomic numbers (and thus different nuclear charges) are known as **isobars**. This is because they have the same total number of nucleons (protons + neutrons) but differ in the number of protons.

### Step 4: Provide Examples
For example, consider the following isobars:
- \(^{40}_{19}K\) (Potassium-40) and \(^{40}_{20}Ca\) (Calcium-40).
Both have a mass number of 40, but Potassium has 19 protons while Calcium has 20 protons, leading to different nuclear charges.

### Step 5: Conclusion
Thus, the answer to the question is that atoms with the same mass number but different nuclear charges are called **isobars**.

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