Q1: A vapor whose partial pressure is less than its equilibrium vapor pressure is called a __________ vapor.

ANS:C - superheated

Superheated refers to a state where a substance, typically a liquid or a vapor, is heated to a temperature above its boiling point at a given pressure, but it remains in the liquid or vapor phase. In other words, the substance is heated beyond the point where it would normally change phase (boil) at that pressure. When a substance reaches its boiling point at a particular pressure, it typically absorbs additional heat energy without undergoing a phase change. This additional heat causes the temperature of the substance to rise above its boiling point. The substance is then considered superheated because it exists as a liquid or vapor at a temperature higher than its boiling point at that pressure. Superheated liquids and vapors are often encountered in industrial processes such as power generation, where steam is superheated to high temperatures to increase its energy content and efficiency. Additionally, superheated water can be found in geothermal systems and in some experimental setups. It's important to note that superheated substances can be unstable. Any disturbance or introduction of impurities can cause rapid boiling or phase transition to occur, releasing stored energy and potentially leading to violent boiling phenomena such as boiling or steam explosions. Therefore, handling superheated substances requires caution and appropriate safety measures.