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Chemistry
Chemistry
Problem
Assertion :
The third period contains only 8 electrons and not 18 like 4th period.
Reason :
In III period filling starts from
3
s
1
3s^1
3
s
1
and complete at
3
p
6
3p^6
3
p
6
whereas in IV period it starts from
4
s
1
4s^1
4
s
1
and complete after
3
d
10
3d^{10}
3
d
10
and
4
s
2
4s^2
4
s
2
.
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