Chemistry NCERT Exemplar Solutions Class 12th Chapter Four

This is a Short Answer Type Question as classified in NCERT Exemplar

Given: Order of the reaction = 0

We know that a zero order reaction is a chemical reaction that occurs regardless of the reactant's concentration.

The rate law of 2A + B→C is

r = k [A]⁰ [B]⁰

For a zero- order reaction

r = k

This is a Short Answer Type Question as classified in NCERT Exemplar

A bimolecular reaction occurs when two particles collide. The product of the concentrations of both elements determines the rate of reaction. If one of the reactants is taken in substantial excess in such a way that its concentration seldom changes, a bimolecular reaction can be kinetically first order.

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Tell us about the pseudo-first-order reaction. It's the reaction with the highest true rate law, yet it behaves like a first order reaction, but it's more specifically a second order reaction.

As an example, consider the hydrolysis of an ester.

CH₃COOC₂CH₅ + H₂O→CH₃COOH + C₂H₅OH

rate = k [CH₃COOC₂H₅] [H₂O]… (constant)

k1 [CH₃COOC₂H₅]

k = k [H₂O] 

This is a Long Answer Type Question as classified in NCERT Exemplar

Average rate depends upon the change in concentration of reactants or products and the time taken for that change to occur. However, the average rate cannot be used to predict the rate of reaction at a particular instance as it would be constant for the time interval for which it is calculated. 

So, to express the rate at a particular moment of time we determine the instantaneous rate. Itis obtained when we consider the average rate at the smallest time interval say dt (i.e. when? t approaches zero). 

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Ans:

As  illustrated in the graph, as the temperature rises, the peak pushes ahead, increasing probable kinetic energy while decreasing the number of molecules utilizing it, resulting in a faster rate of reaction.

 

This is a Long Answer Type Question as classified in NCERT Exemplar

The reaction rate in collision theory is determined by two factors: energy and orientation factor. Certain reactions can be highly exothermic and energetically favoured, meaning the reactants have enough activation energy to collide effectively. However, they do not proceed at a fixed temperature, which is why the reactant molecules are not orientated properly during collisions, resulting in atoms of reactant molecules combining to produce products that do not face each other.