Oxides are defined as which of the following?

• A. compounds containing OH with metal
• B. alkanes
• C. compounds of oxygen with another element
• D. acids

Answer: (C)

Oxides are compounds formed when oxygen combines with another element. The key idea is that the oxide contains oxygen bonded to a second element, regardless of whether that element is a metal or a nonmetal. This includes substances like iron oxide (a metal oxide) and carbon dioxide (a nonmetal oxide). A hydroxide, by contrast, contains the OH group, as in sodium hydroxide, which is not an oxide. Alkanes are hydrocarbons with only carbon and hydrogen, so they’re not oxides. Some oxides can react with water to form acidic or basic solutions, but the defining feature is simply oxygen bonded to another element.