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Question
Write down the electronic configuration of the following elements from the given atomic numbers. Answer the following question with explanation.
1H, 7N, 20Ca, 16S, 4Be, 18Ar Which of these elements belong to the second group?
Solution
1H, 7N, 20Ca, 16S, 4Be, 18Ar
Electronic configuration of the following elements is:
1H = 1
7N = 2,5
20Ca = 2,8,8,2
16S = 2,8,6
4Be = 2,2
18Ar = 2,8,8
20Ca, 4Be belong to second group because these elements have 2 electrons in its outermost shell.
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