Hydrazine (N2H4) is often used as a rocket fuel. It can be produced from the elements by reacting nitrogen gas (N2) with another substance. What is the correct amount of the substance that would react with nitrogen gas to form one mole of hydrazine?
A. H2
B. 2 H2
C. 2NH2
OD. 4 NH

An uncovered pot of water lies out in the sun. which statements correctly describe what happens at the surface of the liquid water? 1. the vapor pressure remains constant regardless of the water temperature. 2. the vapor pressure is produced by water molecules that have evaporated. 3. the vapor pressure increases as the sun heats the water in the pot. 4. evaporation stops once the vapor pressure reaches a certain point. 5. evaporation and condensation both occur on the liquid’s surface.