X and Y are elements in Period 3 of the Periodic Table. • The oxide of X is solid at room temperature, and this oxide has a giant structure. • The chloride of X does not react with water. • Argon is the only Period 3 element with a melting point lower than that of Y. What might the formula of a compound made between elements X and Y be?
- A$\text{Al}_2\text{S}_3$
- B$\text{MgS}$
- C$\text{NaCl}$
- D$\text{PCl}_5$