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Karnataka Board PUCPUC Science Class 11

What are the atomic numbers of elements whose outermost electrons is represented by 3s1.

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Question

What are the atomic numbers of elements whose outermost electrons is represented by 3s1.

Numerical
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Solution

3s1

Completing the electron configuration of the element as

1s2 2s2 2p6 3s1.

∴ Number of electrons present in the atom of the element

= 2 + 2 + 6 + 1 = 11

∴ Atomic number of the element = 11

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Chapter 2: Structure of Atom - EXERCISES [Page 70]

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NCERT Chemistry - Part 1 and 2 [English] Class 11
Chapter 2 Structure of Atom
EXERCISES | Q 2.23 - (ii) (a) | Page 70

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