Which electron configuration represents the element carbon (atomic number 6)? a)1s2 2s2 2p6 b)1s2 2s2 2p4 c)1s2 2s2 2p2 d)1s2 2s2

C) 1s2 2s2 2p2

Explanation:
We are given that carbon has atomic number 6. This means that carbon has 6 electrons.
1- The first level is composed of only one sublevel (s sublevel) and can hold only two electrons. Therefore, the first two carbon electrons will occupy 1s2
2- The second level is composed of two sublevels (s sublevel and p sublevel). The s sublevel can hold only two electrons while the p sublevel can hold up to six electrons. Since only four carbon electrons are to occupy the second level; two of them will be in the s sublevel (2s2) while the other two will occupy the p sublevel (2p2)

Combining the above, we will find that the configuration of carbon is:
1s2 2s2 2p2

Hope this helps :)

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