The occurrence of Reaction Speed

In a chemical reaction during a severe backlash from its original state (start) to the final state is estimated through multiple reaction steps.

Example: 4 HBr (g) + O 2 (g) → 2 H 2 O (g) + 2 Br 2 (g)

From the equation above shows that each 1 molecule of O 2 reacts with 4 HBr molecules. A new reaction can take place if there is a successful collision between the reacting molecules. Collisions as well as between 4 HBr molecules to 1 molecule O 2 less likely to succeed. Collisions that might work is a collision between two molecules is 1 molecule HBr with 1 molecule O 2. This means that the above reactions take place in several stages and the stages are expected to:
Phase 1: HBr + O 2 → HOOBr (slow)
Stage 2: HBr + HOOBr → 2HOBr (fast)
Phase 3: (HOBr + HBr → H 2 O + Br 2) x 2 (fast)
------------------ +
4 HBr + O 2 → 2H 2 O + 2 Br 2

From the above examples it turns out experimentally the reaction rate is determined by the speed of reaction of the formation of the reaction duration HOOBr slowest.

Series of reaction steps in a reaction called "reaction mechanism" and the speed of the reaction keselurahan determined by the slowest reaction in the reaction mechanism. Therefore, this stage is called the stage of determining the reaction rate.