The electronic configurations of three elements X, Y, and Z are X - 2,8; Y - 2, 8, 7 and Z - 2, 8, 2. Which of the following is correct?
(a) X is a metal
(b) Y is a metal
(c) Z is a non-metal
(d) Y is a non-metal and Z is a metal

Academic Chemistry NCERT Class 10

Correct Answer: (d) Y is a non-metal and Z is a metal

Explanation: According to the electronic configuration given above, Y is chlorine (non-metal) and Z is Magnesium (metal).

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Updated on: 10-Oct-2022

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