How can you tell when a solid substace dissolves in water and does not react

Does the temperature affect the solubility of sugar and salt in water? if it does tell me like different temperatures with different solubilities so i can sketch down a graph

What is the percent by mass of oxygen in fe2o3

Consider this equilibrium: n29) + o2(g) + 2no(c).nitrogen gas and oxygen gas react when placed in a closed container. as the reaction proceeds towards equilibrium, what happens to the rate of thereverse reaction?