Which of the following are non-metal oxides?

Which of the following are non-metal oxides?

• A. Al2O3, ZnO
• B. CO2, SO2
• C. CO2, SO2
• D. HCl

Answer: (C)

Non-metal oxides are oxides formed when non-metals bond with oxygen and they usually behave as acidic oxides in water. Carbon and sulfur are non-metals, so their oxides—carbon dioxide and sulfur dioxide—fit this category. In contrast, oxides of metals like aluminum oxide and zinc oxide tend to be basic or amphoteric, not acidic. Hydrogen chloride isn’t an oxide at all; it’s a hydrogen halide and contains no oxide oxygen. So the oxides that are non-metal oxides here are CO2 and SO2.

Non-metal oxides are oxides formed when non-metals bond with oxygen and they usually behave as acidic oxides in water. Carbon and sulfur are non-metals, so their oxides—carbon dioxide and sulfur dioxide—fit this category. In contrast, oxides of metals like aluminum oxide and zinc oxide tend to be basic or amphoteric, not acidic. Hydrogen chloride isn’t an oxide at all; it’s a hydrogen halide and contains no oxide oxygen. So the oxides that are non-metal oxides here are CO2 and SO2.