Question

If periodic table has total 10 periods then number of subshell present in 8th period will be
a- 7
b- 4
c- 5
d- 6​

Answer 1

To find :- The number of sub shell present in 8th period if periodic table has total 10 periods

Solution :-  According to the periodic table,

No of periodic table                                           No of sub shell

1st period                                 -                                1 s

2nd period                               -                              2 s, 2 p

3rd period                                 -                             3 s, 3 p

4th period                                 -                             3 d, 4 s, 4 p

5th period                                  -                            4 d, 5 s, 5 p

6th period                                  -                            4 f, 5 d, 6 s, 6 p

7th period                                  -                             5 f, 6 d, 7 s, 7 p

8th period                                  -                             5 g, 6 f, 7 d, 8 s, 8 p

Hence , there is 5 sub shell in 8th period if periodic table has total 10 periods .

Answer:- option c) 5.

Answer 2

Number of subshells present in 8th period will be 4.

Option (b) is correct.

Explanation:

The principal quantum number of 4th period is 4.

Now the number of subshells in the 4th period will be 4s and 3p.

The pattern of electron filling in the subshell is given as (n - 1)p, (n - 2)d, (n - 3)f, (n - 4)f ..... and so on.

• 1st period ⇒1s
• 2nd period ⇒2s
• 3rd period ⇒3s, 2p
• 4th period ⇒4s, 3p
• 5th period ⇒5s, 4p, 3d
• 6th period ⇒6s, 5p, 4d
• 7th period ⇒7s, 6p, 5d, 4f
• 8th period ⇒8s, 7p, 6d, 5f

Thus the number of subshells in 8th period will be 4.