The questions given below contain statement -1 (Assertion ) and statement -2 (Reason ) . It has four options (a), (b) , ( c) and (d ) out of which ONLY ONE is correct . Choose the correct option as.
Statement -1 . Sixth period is the longest period in the periodic table.
Statement -2 . Sixth period involves the filling of all the orbitals of the sixth energy level

Options

A. Statement -1 is True Statement -2 is True , Statement -2 is correct explanation for Statement -1
B. Statement -1 is True Statement -2 is True , Statement -2 is not a correct explanation for Statement -1
C. Statement -1 is True Statement -2 is False
D. Statement -1 is False Statement -2 is True

Explanation

To solve the given question, we need to analyze both statements and determine their validity.

### Step 1: Analyze Statement 1
**Statement 1:** "The sixth period is the longest period in the periodic table."

- In the periodic table, the sixth period contains a total of 32 elements. This includes:
- 2 elements from the s-block (6s1 and 6s2)
- 10 elements from the d-block (5d1 to 5d10)
- 14 elements from the f-block (4f1 to 4f14)
- 6 elements from the p-block (6p1 to 6p6)

Since the sixth period has the highest number of elements compared to other periods, **Statement 1 is true.**

### Step 2: Analyze Statement 2
**Statement 2:** "The sixth period involves the filling of all the orbitals of the sixth energy level."

- The sixth period does involve the filling of the 6s, 5d, 4f, and 6p orbitals. However, it does not fill all orbitals of the sixth energy level because:
- The 5d and 4f orbitals are from the lower energy levels (n=5 and n=4 respectively).
- The sixth energy level (n=6) only includes the 6s and 6p orbitals.

Since not all orbitals of the sixth energy level are filled in the sixth period, **Statement 2 is false.**

### Conclusion
- Statement 1 is true.
- Statement 2 is false.

### Final Answer
The correct option is (a): Statement 1 is true, Statement 2 is false.

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