when discussing Solutions the amount of solute dissolved in the solvent is important to know as it will affect the colligative properties of a solution a pure illusion prepared by dissolving the maximum amount of solute in a given amount of solvent is best described as​

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.