Question
Question: During the decomposition of hydrogen peroxide, glycerine acts as a positive catalyst. A) True B)...
During the decomposition of hydrogen peroxide, glycerine acts as a positive catalyst.
A) True
B) False
Solution
In a decomposition of hydrogen peroxide, it gets broken into water and oxygen and the reaction gets speed up by using positive catalyst and the other type of catalyst is negative catalyst. It decreases the rate of reaction and glycerine reduces the rate of decomposition of hydrogen peroxide.
Complete step by step answer:
Catalysis is the change in speed or rate of a chemical reaction due to the help of a catalyst but a catalyst is not consumed by the reaction itself. Catalysts that speed up the rate of chemical reaction are known as positive catalysts. Substances that increase the activity of catalysts are called promoters. Most catalysts work by lowering the activation energy of the reaction which speeds up the reaction by reducing the amount of energy used. An example is manganese oxide (MnO2) which is added to hydrogen peroxide(H2O2) and the hydrogen peroxide splits into water and oxygen.
Hydrogen peroxide is a chemical compound with the formula H2O2 . In its pure form, it is a very pale blue liquid which is slightly more viscous than water. It is unstable and slowly decomposes in the presence of light and it is stored with a stabilizer in a weakly acidic solution in a dark coloured bottle. The rate of decomposition increases with rise in temperature, concentration and pH. Decomposition of hydrogen peroxide is catalysed by various compounds including most transition metals and their compounds such as manganese dioxide, silver and platinum. Non-metallic catalysts include potassium iodide which reacts rapidly with it.
Hence, the decomposition of hydrogen peroxide is suppressed by adding glycerol to the solution of it. Thus, glycerine or glycerol acts as a negative catalyst.
Therefore, option B is correct.
Note: Remember that a positive catalyst increases the rate of a reaction and negative catalyst decreases its rate or speed. In a decomposition of hydrogen peroxide, potassium iodide or compounds of transition metals acts a positive catalyst and glycerine acts a negative catalyst.