Question 10
In PCl5 the phosphorus atom forms five bonds, giving ten electrons around it. What does this show?
The right answer is the one marked above.
The octet has been exceeded. Ten is more than eight, so this is a case where an atom holds more than an octet in its valence shell.
A complete octet would be exactly eight, and an incomplete one fewer than eight — that is AlCl3, not this. The bonds are covalent: phosphorus and chlorine share pairs rather than transferring electrons.