Question

Write the atomic number of the element present in the third period and seventeenth

Answer 1

atomic no: 17

chlorine

Answer 2

Explanation:

General configuration for seventeenth group elements is ns^2np^5. In the third period, the principal quantum number for valance shell for the given elements is 3s^2,3p^5. Third period starts from atomic number, Z = 11 and end at Z = 18. Hence, the atomic number of the given element is 10+7=17.

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