According to your textbook, how many of the following are properties of covalent compounds:
a. *can be gas, liquid or solid at room temperature
b. *does not conduct electricity
c. *exist as an extended array of atoms
d. *involves the sharing of electrons

a, b and d are correct.

Explanation:

There are two types of attractive forces in covalent compounds:

Because intermolecular forces are usually quite weak compared with the forces holding atoms together within a molecule, molecules of a covalent compound are not held together tightly. Consequently, covalent compounds are usually gases, liquids, or low-melting solids.

Most covalent compounds aqueous solutions generally do not conduct electricity, because the compounds are nonelectrolytes.