# What is electronic configuration of an element of an element 12X​21

Dear Student,

Representation of element 12X21

Atomic Number of element = 12

Atomic mass of element = 21

Number of electron = Number of Proton = 12

Number of neutron = 9

Electronic configuration = 1s2 2s2 2p6 3s2

Regards

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can u make the question clearer?

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2,8,8,3
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THE ATOMIC NUMBER IS 12 SO IT HAS 12 TOTAL ELECTRONS IN ITS SHELLS AND ITS ATOMIC MASS 21 WHICH MEANS IT HAS 12 PROTONS AND 7 NEUTRONS IN THE NUCLEUS .
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THE ATOMIC NUMBER IS 12 SO IT HAS 12 TOTAL ELECTRONS IN ITS SHELLS AND ITS ATOMIC MASS 21 WHICH MEANS IT HAS 12 PROTONS AND 7 NEUTRONS IN THE NUCLEUS .
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Electronic configuration of an element states the number of electrons present in different shells or orbits of  an atom of element.
For example Electronic configuration of Sodium (Na)-2,8,1
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THE ATOMIC NUMBER IS 12 SO IT HAS 12 TOTAL ELECTRONS IN ITS SHELLS AND ITS ATOMIC MASS 21 WHICH MEANS IT HAS 12 PROTONS AND 7 NEUTRONS IN THE NUCLEUS .
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