Smart! We have $$5$$ electrons. The $$n=1$$ orbit can have a maximum of $$2$$ electrons. So, we put the $$2$$ electrons there. We can't put more electrons into this orbit. So, the $$3$$ electrons have to go to the $$n=2$$ orbit, as this orbit can have a maximum of $$8$$ electrons.
• $$2$$ in $$n=1$$, $$8$$ in $$n=2$$ and $$4$$ in $$n=3$$
• $$2$$ in $$n=1$$, $$6$$ in $$n=2$$ and $$4$$ in $$n=3$$
• $$2$$ in $$n=1$$ and $$8$$ in $$n=2$$
• $$2$$ in $$n=1$$ and $$4$$ in $$n=2$$