If an atom has seven electrons how many are in the second shell?

A. 2

B. 5

C. 7

D. You need to know the number of protons to figure this out.

5 electrons because first shell can only have two electrons and second can hold up until 8

If it had seven electrons then we know that the first energy lever has to have two and no more and so it would be 5 as you will only have 5 left. if you had more then 8 then there would be three but these not so your fine! 5 electrons on other shell