So two electrons go into the one s, two electrons go into the two s, and five electrons go into the two p. Now, H stays the same because H is neutral. And so we place one electron into our one s orbital. So let's begin by first counting the total amount of balanced electrons that we have. Remember, balanced electrons are those electrons found in the outermost energy shell. For oxygen, that happens to be the N equals two shell. So two plus five equals seven.