A @[email protected] corresponding to the rate of @[email protected] of the reacting @[email protected] This is also known as '@[email protected]' since rates of @[email protected] are themselves controlled by @[email protected] rates (which in turn depend on the @[email protected] of the @[email protected] and the dimensions of the reactant molecular entities). For a @[email protected] reaction between solutes in water at \(25\ ^{\,\unicode{x26ac}}\text{C}\) an @[email protected] rate is calculated to have a second-order @[email protected] of about \(10^{10}\ \text{dm}^{3}\ \text{mol}^{-1}\ \text{s}^{-1}\).