Q. Assertion : The element having with electronic configuration 1s2 2s2 2p6 3s2 and 1s2 2s2 belong to the same group
Reason: Both have same number of electrons in the valence shell
Solution:
Elements having same number of valence shell are present in same group.
Here, each elements have 2 valence electrons.
So, both lie in the same group, i.e., group 2 (alkaline earth metals)
Hence both assertion and reason are correct and reason is correct explanation of assertion.
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