Question

Assertion(A): Sodium belongs to IIA group.
Reason(R): The electronic configuration of Sodium is 1s² 2s² 2p⁶ 3s¹
a) Both A and R are true and R is the correct explanation of A
b) Both A and R are true and R is not the correct explanation of A
c) A is correct and R is incorrect
d) A is incorrect and R is correct ​

Answer 1

Answer:

ANSWER

A number of electrons present in valence shell of penultimate Shell represents the group of elements.

For s block elements: no.of group=number of valence shell electron.

p block elements: no. of group= 2 + 10 + number of valence electrons.

d block elements: no. of group= number(n-1)d electrons + number of electrons in nth shell.

Here, the differential electron is in p orbital hence, it belongs to p block

No. of group= 2+ 10 + 3=15 i.e 15th group or VA group

Answer 2

Answer:

d

Explanation:

Because Na is from lA group and electronic configuration is correcr