Final answer:
To determine whether a compound is covalent or ionic, you need to consider the elements involved. Both CO and SO2 are covalent compounds because the elements are nonmetals. LiF, ZnS, and Fe2O3 are ionic compounds because they involve a metal and a nonmetal.
Step-by-step explanation:
In order to determine whether a compound is covalent or ionic, we need to look at the elements involved in the compound. If the elements are both nonmetals, then the compound is covalent. If one element is a metal and the other is a nonmetal, then the compound is ionic.
a. CO is covalent because both carbon and oxygen are nonmetals. LiF is ionic because lithium is a metal and fluorine is a nonmetal.
b. ZnS is ionic because zinc is a metal and sulfur is a nonmetal. SO2 is covalent because both sulfur and oxygen are nonmetals.
c. BF3 is covalent because boron and fluorine are nonmetals. Fe2O3 is ionic because iron is a metal and oxygen is a nonmetal.