Galen lists the properties of four covalent compounds and two ionic compounds in the table below. Compounds Boiling point °C Elemental composition Type of compound
H2O 100.0 all nonmetals covalent
CS2 46.3 all nonmetals covalent
CH4 −161.5 all nonmetals covalent
HCl −85.1 all nonmetals covalent
NaCl 1413.0 a metal and a nonmetal ionic
KCl 1420.0 a metal and a nonmetal ionic

If his teacher asks him about a different covalent compound, what can he predict about its properties? Select all that apply.

A.
It consists of all metals.

B.
It has a high boiling point.

C.
It has a low boiling point.

D.
It consists of all nonmetals.

E.
It consists of all semimetals.

F.
It consists of nonmetals and metals.