The isotopes of neutral atom of an element differ in

Options

A. electron and proton
B. neutron and electron
C. neutron, electron and proton
D. neutron and proton

Answer

To answer the question "The isotopes of a neutral atom of an element differ in," we will follow these steps:

### Step-by-Step Solution:

1. **Understanding Isotopes**:
Isotopes are variants of a particular chemical element that have the same number of protons but different numbers of neutrons. This means that isotopes of an element have the same atomic number but different mass numbers.

2. **Atomic Number and Mass Number**:
- The **atomic number** (Z) is the number of protons in the nucleus of an atom and determines the identity of the element.
- The **mass number** (A) is the total number of protons and neutrons in the nucleus.

3. **Example of Isotopes**:
A common example is carbon, which has two stable isotopes: Carbon-12 (C-12) and Carbon-13 (C-13).
- C-12 has 6 protons and 6 neutrons (mass number = 12).
- C-13 has 6 protons and 7 neutrons (mass number = 13).
Here, both isotopes have the same atomic number (6) but different mass numbers (12 and 13).

4. **Conclusion**:
Therefore, the isotopes of a neutral atom of an element differ in their mass number due to the difference in the number of neutrons.

### Final Answer:
The isotopes of a neutral atom of an element differ in their mass number.

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