Question
Question: Half-life period of a zero order reaction is: A. Directly proportional to initial concentrations o...
Half-life period of a zero order reaction is:
A. Directly proportional to initial concentrations of reactants
B. Independent of initial concentrations of reactants
C. Inversely proportional to initial concentrations of reactants
D. Inversely proportional to the square of initial concentrations of reactants
Solution
The order of reaction can be defined as the power dependence of rate on the concentration of all reactants.
In order to determine the reaction order, the power-law form of the rate equation is used.
Is given by r=k[A]x[B]y.
In the expression described above, ‘r’ refers to the rate of reaction, ‘k’ is the rate constant of the reaction, [A] and [B] are the concentrations of the reactants. The exponents of the reactant concentrations x and y are referred to as partial orders of the reaction. Therefore, the sum of all the partial orders of the reaction yields the overall order of the reaction.
Law of mass action: It states that the rate of the reaction is proportional to the product of concentration of reactant
In Zero Order Reactions: The rate of reaction is independent of the concentration of the reactants in these reactions.
A change in the concentration of the reactants has no effect on the speed of the reaction
Examples of these types of reactions include the enzyme-catalyzed oxidation of CH3CH2OH (ethanol) to CH3CHO (acetaldehyde).
Complete step by step answer:
Half life time: The time in which the concentration of a particular reactant is reduced to half of its initial value.
Half-life of zero order reaction is given by t21=2ka
Where 'a' is the initial concentration of reactants.
half-life of zero order reaction is directly proportional to the initial concentration of reactants.
So, the correct answer is Option A.
Note: It can be noted that when the order of reaction is a diffraction, the reaction is generally a chain reaction or follows some other complex mechanism.
Characteristics of the reaction order for a chemical reaction are:
1. Order of reaction is just a mathematical number that signifies the effect of change of concentration on the rate of reaction.
2. It is determined experimentally.
3. If one doubles the concentration of reactant, the rate of reaction becomes double. Then, it is called first order kinetic.
4. If on doubling the concentration of reactant, the rate of reaction becomes four times then it is called second order kinetics.
5. If on changing the concentration of reactant, the rate of reaction does not change then it is called zero order kinetics.