Question

Use the periodic table to complete the activity.

The periodic table of elements shows element groups, periods, and element properties.

In 3–5 sentences, predict how phosphorus and chlorine would bond. Explain why they would bond that way.

(4 points)

Answer 1

Phosphorus (group 15) has five valence electrons and chlorine (group 17) has seven, so P needs three electrons and each Cl needs one to complete an octet. They will form covalent bonds: typically one P shares electrons with three Cl atoms to make PCl3, with each P–Cl pair sharing a pair of electrons. Because both are nonmetals the electrons are shared rather than fully transferred, and the bonds are polar covalent since Cl is more electronegative than P. (Phosphorus can also expand its octet in some cases to form PCl5 with five P–Cl bonds.)