Activation energy for the acid catalysed hydrolysis of sucrose is 6.22 kJ ${{mol}^{-1}}$ while the activation energy is only 2.16 kJ ${{mol}^{-1}}$ when hydrolysis is catalysed by the enzyme sucrose. Explain.
Enzymes are the essential biological catalysts which are needed to catalyse biochemical reactions. Enzymes are needed only in small quantities for the progress of a reaction. Like chemical catalysts, enzymes reduces the magnitude of activation energy by providing alternative pathway, e.g. hydrolysis of sucrose, the enzyme sucrose reduces the activation energy from 6.22 k] ${{mol}^{-1}}$ to 2.15 kJ ${{mol}^{-1}}$. Thus, enzyme catalysed reactions occur at a much faster rate.