Question

1.
Assertion (A): Second period consists of 8 elements.
Reason (R) : Number of elements in each period is four times the number of atomic orbitaks
available in the energy level that is being filled.
a) Assertion and reason are correct and reason is the correct explanation of assertion
b) Assertion and reason are correct but reason is not the correct explanation of assertion
c) Assertion is correct but reason is incorrect
d) Assertion is incorrect but reason is correct.​

Answer 1

Answer:

Answer is c)

Explanation:

Assertion (A) is correct.

But Reason(R) is wrong

This is because each sub-shell can have a maximum of two electrons of opposite spin.

Thus, We can simply say that, Number of elements is 2 times of the number of sub-shell present in that energy level..

For example:

For 3rd period, Number of atomic orbitals present = 3 ( 3s, 3p, 3d)

Whereas, Number of elements on 3rd group is 8.

Hope you understand it...!!!!

Answer 2

In the given question, the assertion is correct but the given reason is false

• The periodic table consists of elements that are arranged in order and given certain atomic numbers.
• In the second period of the periodic table, 8 elements can be found namely, Li, Be, B, C, N, O, F, Ne.
• The number of elements that are there in every period can be calculated by multiplying the number of atomic orbitals available in the energy level being filled twice.

Thus, in the given question (Option c) Assertion is correct but the reason is incorrect is the answer.