How many electrons does a Co atom have in its 3𝑑 subshell? & How many of those electrons are unpaired?

Question

How many electrons does a Co atom have in its 3𝑑 subshell?

1. number of electrons: ? 3d electrons

How many of those electrons are unpaired?

1. number of unpaired electrons: ? unpaired electrons

Answer 1

Co is atomic number 27 meaning it has 27 protons and 27 electrons.

The electron configuration for Co can be written as

1s2 2s2 2p6 3s2 3p6 3d7 4s2

1). So there are SEVEN 3d electrons

2). To see the unpaired electrons, view the block diagram:

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4s 3d

Thus there are THREE unpaired electrons