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