So in liquid reactants are dissolved in a solvent, like, for example, water, which ends up predominating the solution. Therefore, most of the collisions in liquids occur between solvent and solute. And this means that even though the collisions occur more frequently in liquid than acoustic solutions, a lot of those collisions are between solvent and soluble molecules. And the only way you react molecules is if the reactive molecules react. So, because most of the collisions occur between solid molecules and solid molecules, that means, on average, reactions in the gas state and liquid state will be approximately the same. Now let's look at this Cage effect.