Answer:
See explanation
Step-by-step explanation:
Period 3 elements include; Na, Mg, Al, Si, P,S,Cl and Ar
Across the period, the chlorides of the elements change from solid to gas. The chlorides of metals are solid while the chlorides of non metals are gaseous.
Also, the chlorides become more volatile across the period. The formulas of the chlorides change from MCl to MCl2 to MCl3 to MCl4, MCl5 and MCl6 respectively across the period where M is a period 3 element.
The pH of the solutions of chlorides of period 3 elements change from neutral to acidic across the period. The pH of the chlorides of metals are neutral while the chlorides of the nonmetals usually yield acid solutions.