English

For the reaction A + B → P. If [B] is doubled at constant [A], the rate of reaction doubled. If [A] is triple and [B] is doubled, the rate of reaction increases by a factor of 6. Calculate the rate - Chemistry

Advertisements
Advertisements

Question

For the reaction A + B → P.
If [B] is doubled at constant [A], the rate of reaction doubled. If [A] is triple and [B] is doubled, the rate of reaction increases by a factor of 6. Calculate the rate law equation.

Numerical

Solution

Given:

A + B → P

∴ Rate of reaction,

rate = k[A]x [B]y    ...(i)

If [B] is doubled at constant [A], the rate of reaction doubled.

∴ 2 × rate = k[A]x [2B]y

∴ 2 × rate = k[A]x 2y [2B]y    ...(ii)

If [A] is tripled and [B] is doubled, the rate of reaction increased by a factor of 6.

∴ 6 × rate = k[3A]x [2B]y   

6 × rate = 3x k[3A]x 2y [B]y    ...(iii)

Divide equation (ii) by (i), we get

`(2 xx "rate")/"rate" = (k[A]^x  2^y[B]^y)/(k[A]^x  [B]^y)`

21 = 2y

∴ y = 1

Now divide equation (iii) by (i), we get

`(6 xx "rate")/"rate" = (3^x  k[A]^x  2^y [B]^y)/(k[A]^x  [B]^y)`

6 = 3x2y

= 3x × 2    ...(∵ y = 1)

∴ x = 1

Now, x = 1 and y = 1 values should be written in equation (i)

∴ Rate law can be written as:

rate = k[A]1 [B]1

shaalaa.com
Rate of Reaction and Reactant Concentration
  Is there an error in this question or solution?
2023-2024 (March) Official

RELATED QUESTIONS

Choose the most correct option.

The order of the reaction for which the units of the rate constant are mol dm-3 s-1 is _______.


Choose the most correct option.

The rate constant for the reaction \[\ce{2N2O5_{(g)} -> 2N2O4_{(g)} + O2_{(g)}}\] is `4.98 xx 10^-4 "s"^-1`. The order of reaction is _____________.


What is the half life of a first order reaction if time required to decrease concentration of reactant from 0.8 M to 0.2 M is 12 h?


Choose the most correct option.

The elementary reaction \[\ce{O3_{(g)} + O_{(g)} -> 2O2_{(g)}}\] is ___________.


Choose the most correct option.

Rate law for the reaction, \[\ce{2NO + Cl2 -> 2NOCl}\] is rate = k[NO2]2[Cl2]. Thus of k would increase with _____________.


Answer the following in one or two sentences.

For the reaction, \[\ce{CH3Br_{(aq)} + OH^{-}_{(aq)} -> CH3OH^{\ominus}_{(aq)} + Br^{\ominus}_{(aq)}}\], rate law is rate = \[\ce{k[CH3Br][OH^\ominus]}\]

How does reaction rate changes if \[\ce{[OH^\ominus]}\] is decreased by a factor of 5?


Answer the following in one or two sentences.

For the reaction,

\[\ce{CH3Br_{(aq)} + OH^-_{ (aq)} -> CH3OH^-_{ (aq)} + Br^-_{ (aq)}}\], rate law is rate = k`["CH"_3"Br"]["OH"^-]`

What is the change in rate if concentrations of both reactants are doubled?


A First order reaction is 50% complete in 69.3 minutes. Time required for 90% completion for the same reaction is _______.


Write four key points about order of reaction.


Define order of reaction with suitable examples.


In a first-order reaction A → B, 60% of a given sample of a compound decomposes in 45 mins. What is the half-life of reaction? Also, write the rate law equation for the above first-order reaction.


In a hypothetical reaction,

\[\ce{2A + B -> Products}\]. Rate = k [A]2 [B]

Molar concentration of 'B' is kept constant and molar concentration of 'A' is tripled, then the rate of reaction will ____________.


A gaseous hypothetical chemical equation \[\ce{2A ⇌ 4B + C}\] is carried out in a closed vessel. The concentration of B is found to increase by 5 × 10−3 mol dm−3 in 10 second. The rate of ____________.


For a chemical reaction rate law is, rate = k[A]2[B]. If [A] is doubled at constant [B], the rate of reaction ______.


For a hypothetical reaction \[\ce{A + B -> C}\], it is found that doubling the concentration of A increases the rate by 8 times and doubling the concentration of B increases the rate by 4 times. The overall order of the reaction is ____________.


The rate law for the reaction \[\ce{A + B + C -> Product}\] is expressed as Rate = k[A]2 [B]1 [C]0. What is the overall order of the reaction?


Consider the reaction \[\ce{2A + 2B -> C + 2D}\], if concentration of A is doubled at constant [B], rate increases by a factor 4. If concentration B is doubled at constant [A] the rate is doubled. Rate law of the reaction is ____________.


In the reaction \[\ce{A + B2 -> AB + B}\], the rate of reaction is directly proportional to the concentration of A and independent on the concentration of B2. What is the rate law expression?


The reaction \[\ce{A + B -> P}\], is second order in A and first order in B. What is the rate law for the reaction?


What is the molecularity and order of the following reaction if rate law is, rate = k[O3][O] respectively.

\[\ce{O_{3(g)} + O_{(g)} -> 2O_{2(g)}}\]


For the reaction \[\ce{2A + B -> 3C + D}\], which among the following is NOT the correct rate law expression?


Which of the following unit is used to express the rate of a reaction?


The correct order of raaii of F, F-, O and O2- is ______.


For a chemical reaction A → 7 products, the rate of reaction doubles when the concentration of A is increased by a factor 4. The order of the reaction is ______.


The rate constant of a reaction ______.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×