Suppose an element has a valence of 2 and an atomic number of 27. Based only...

Suppose an element has a valence of 2 and an

atomic number of 27. Based only on the quantum

numbers, how many electrons must be present in

the 3d energy level?

Expert Solution

Atomic no 27 is Cobalt

Co - E.C = 1s2 2s2 2p6 3s2 3p6 4s2 3d7

Valency is 2 so it is Co^2+

Co^2+ - E.C = 1s2 2s2 2p6 3s2 3p6 4s0 3d7

No of electrons in 3d energy level will be 7 because the two electrons would be removed from outermost shell i.e 4s

queen_honey_blossom answered 2 years ago

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