PLZ HELP ITS A TIMED ASSIGNMENT Are these empirical formulas or molecular formulas

When balancing a chemical equation:

What happens when an atom of sulfur combines with two atoms of chlorine to produce sci2? a. each chlorine atom shares a pair of electrons with the sulfur atom. b. an electron is transferred from each chlorine atom to the sulfur atom. c. an electron is transferred from the sulfur atom to each chlorine atom. d. each chlorine atom shares all its valence electrons with the sulfur atom.

Air can be considered a mixture. which statement does not explain why?