Question 6
What is the maximum number of electrons the third energy level (M) can hold?
The right answer is the one marked above.
18. The maxima run 2, 8, 18, 32 for levels 1, 2, 3 and 4.
8 is the answer to a different question, and the one people confuse it with: 8 is the most the third level may hold while it is the outermost level. That is why potassium is 2, 8, 8, 1 rather than 2, 8, 9.