A : Isotopes of an element have almost similar chemical properties
R : isotopes have same electron configuration .

Options

A. IF both assertion & reason are true and the reason is the correct explanation of the assertion then mark
B. IF both assertion & reason are true but the reason is not the correct explanation of the assertion , then mark
C. IF assertion is true statement but reason is false , then mark
D. If both assertion and reason are false statements then mark

Answer

To analyze the statements provided in the question, we will break down the assertion (A) and the reason (R) step by step.

### Step-by-Step Solution:

1. **Understanding Isotopes**:
- Isotopes are variants of a particular chemical element that have the same number of protons (atomic number) but different numbers of neutrons, resulting in different mass numbers.

2. **Assertion (A)**: "Isotopes of an element have almost similar chemical properties."
- This statement is **True**. Isotopes of the same element exhibit similar chemical behavior because they have the same number of electrons and the same electron configuration, which are the primary determinants of chemical properties.

3. **Reason (R)**: "Isotopes have the same electron configuration."
- This statement is also **True**. Since isotopes have the same atomic number, they possess the same number of electrons, leading to identical electron configurations.

4. **Relationship between A and R**:
- The reason (R) explains why the assertion (A) is true. The similarity in chemical properties among isotopes is due to their identical electron configurations.

5. **Conclusion**:
- Both the assertion and the reason are true, and the reason correctly explains the assertion. Therefore, the correct option is that both statements are true, and the reason is the correct explanation of the assertion.

### Final Answer:
Both the assertion (A) and the reason (R) are true, and R is the correct explanation of A.

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