Consider the n = 3 energy level in a hydrogen atom. how many electrons can be placed in this level?

18 electrons

Explanation:

There can be up to 2 electrons in 1 orbital.

In the level 3, there are 3 sublevels: 3s, 3p and 3d.

The total number of electrons is 2 + 6 + 10 = 18 e⁻.

Alternatively, we can find the number of electrons in a level using the formula:

2n² = 2 × 3² = 2 × 9 = 18 electrons

let that person have a turn to speak : )