The rate of decomposition of hydrogen peroxide decreases in presence of

Explanation

(i) The chemical reaction in which two or more products are formed from a single reactant is called decomposition reaction. Hydrogen peroxide decomposes into water and oxygen.
`{:(2H_(2)O_(2(l))to 2H_(2)O_((l))+O_(2)uarr),("Hydrogen" " ""Water" " ""Oxygen"),("peroxide"):}`
(ii) The decomposition of hydrogen peroxide into water and oxygen takes place slowly at room temperature. However, the rate of this chemical reaction can be increased on adding manganese dioxide `(MnO_(2))` powder in it, here manganese dioxide acts as a catalyst.