Isotopes have

Options

A. same physical and chemical properties
B. same physical properties but different chemical properties
C. same chemical properties but different physical properties
D. different physical and chemical properties.

Explanation

### Step-by-Step Solution:

1. **Definition of Isotopes**: Isotopes are variants of a particular chemical element that have the same number of protons (atomic number) but different numbers of neutrons, leading to different atomic masses.

2. **Same Atomic Number**: Since isotopes have the same atomic number, they have the same number of electrons. This means that they will exhibit the same chemical behavior because chemical properties are primarily determined by the electron configuration.

3. **Different Atomic Mass**: The difference in the number of neutrons results in different atomic masses for the isotopes. This difference affects their physical properties, such as density, melting point, and boiling point.

4. **Chemical vs. Physical Properties**: Because isotopes have the same electron configuration, they will have identical chemical properties. However, their different atomic masses lead to variations in physical properties.

5. **Example of Isotopes**: A common example is the isotopes of hydrogen: protium (1H), deuterium (2H), and tritium (3H). All have the same atomic number (1) but different atomic masses (1, 2, and 3 respectively). They exhibit similar chemical properties but differ in physical properties like boiling and melting points.

### Conclusion:
Isotopes have the same chemical properties but different physical properties due to their identical atomic numbers and varying atomic masses.

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