(a) What is the number of valence electrons in the atoms of first element in a period?
(b) What is the usual number of valence electrons in the atoms of the last element in a period?

Academic Chemistry NCERT Class 10

(a) The number of valence electrons in the atoms of the first elements in a period is 1.

(b) The usual number of valence electrons in the atoms of the last element (inert gas) in a period is 8.

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Updated on: 10-Oct-2022

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