Chemistry 2 : Hoes does catalyst react ?

Example :

1. Heat up potassium chlorate to release oxygen.

* When potassium chlorate is heated, (figure2) no oxygrn is released. But, when copper (II) oxide is added into the potassium chlorate, the pglowing wooden splinter bursts into flame. It shows copper (II) oxide speed up the decomposition of potassium chlorate to release oxygen.

2KIO3 (S) → 2KLC（S）+ 302 （G）
                                              

Figure2

2. Decomposition of hydrogen peroxide

    Hydrogen peroxide decomposes according to the following equation:

               2H2O2 → 2H2O (L) + O2(G)

At the room temperature , oxygen gas is formed slowly. But when a small amount of manganese (IV) oxide is addedto the solution, the reaction accelerates and the glowing splinter bursts into flame.

Figure3

Figure 3 shows the progress of reaction for the decomposition. Based on the figure 3, a catalyst provides an alternative path for reactant, that has a lower activation energy.

From the collision theory :

* The presence of a catalyst quickens the rate of reaction.

*Presence of a catalyst lowers the activation energy.

*More reactant particles will have activation energy, so there will be more effectives collisions when they collide .

*The rate of reaction will be higher.