Question

The order of reaction is decided by
(A) temperature
(B) mechanism of reaction as well as relative concentration of reactants
(C) molecularity
(D) pressure

Answer 1

The connection between the pace of a chemical reaction and the concentration of the species involved is referred to as the order of reaction. The rate expression (or rate equation) of the reaction in issue must be acquired before the reaction order can be determined. The full composition of the mixture of all the species in the reaction can be understood after the rate equation is determined.

Complete Step By Step Answer:
The number of species whose concentration directly influences the pace of reaction is represented by reaction order.
All the exponents of the concentration variables in the rate expression may be added to get it.
The stoichiometric coefficients corresponding to each species in the balanced reaction have no bearing on the reaction sequence.
A chemical reaction's reaction sequence is always determined by reactant concentrations rather than product concentrations.
The order of reaction can be expressed as an integer or as a fraction. It is even possible for it to have a value of zero.
1. Mechanism of reaction - In the event of a complicated reaction, the order of reaction is determined by the total power of the reactants on the slowest path.
2. Relative concentration of reactants = If the power of reactants equals the relative concentration of reactants, the order may be determined by adding the relative concentrations of reactants.
As a result, [B] is the right answer.

Note:
A reaction's order does not have to be an integer. The following are probable orders: A zero order indicates that a species' concentration has no effect on the rate of a reaction.
Negative integer: A negative order implies that a species' concentration impacts the rate of a reaction inversely.
A positive integer implies that the concentration of a species has a direct impact on the rate of a reaction.
Non-Integer: Positive and negative non-integer orders reflect more complicated connections between concentrations and rate in more complex processes.