In equation He +Br2------>2HI why chemical rate of Br2 is taken as 1/2 . It's a reversible reaction. Please explain in detail. While H2 rate is taken as 1 why?
He +Br2------>2HI ?????? Just what have you been doing all night?
H2+Br2>>>>2HBr
So the rate of Br2 as 1/2 power? Maybe because the reaction is simplified, because if you look at it in more detail, it is to 3/2 power.
http://www.esf.edu/chemistry/dibble/fch361/info/H2Br2PSSA.pdf
In a chemical reaction, the rate of the reaction is determined by the rate at which the reactants are consumed or the rate at which the products are formed. The rate of a reaction is often determined experimentally by measuring the change in concentration of the reactants or products over time.
In the equation He + Br2 → 2HI, the reaction indicates that one molecule of helium (He) reacts with one molecule of bromine (Br2) to produce two molecules of hydrogen iodide (HI). Since the coefficient of Br2 is 1 in the balanced equation, it suggests that only one molecule of bromine is used in the reaction.
However, when a reaction is reversible, it means that it can proceed in both the forward and reverse directions. In this case, the reverse reaction is: 2HI → He + Br2. The balanced equation for the reverse reaction indicates that two molecules of hydrogen iodide react to produce one molecule each of helium and bromine.
When determining the rate of a reversible reaction, it is important to take into account the stoichiometry of the reaction. The rate of the forward reaction is determined by the consumption of bromine (Br2), and since the coefficient of Br2 is 1, we consider its rate as 1. However, since the reverse reaction involves the formation of bromine, its rate is considered as 1/2, as it consumes two molecules of hydrogen iodide.
Regarding the rate of hydrogen (H2), we need to consider the stoichiometry of the reaction as well. In the balanced equation, two molecules of HI are formed for each molecule of H2 consumed. Therefore, the rate of H2 is taken as 1 because it is stoichiometrically equivalent to the formation of HI.
To summarize:
- The rate of Br2 is taken as 1/2 because, in the reverse reaction, 2HI are required to form one molecule of Br2.
- The rate of H2 is taken as 1 because, in the forward reaction, one molecule of H2 is consumed to form two molecules of HI.