Rates of Reactions

Try this 4 question quiz

- Define rate
- Define order of a reaction
- The rate law for a reaction is as given

Rate = k [A]^{2}[B]

What is the order with respect to A, What is the order with respect to B, What is the overall order?

- For a multi step reaction how will you determine the order of a reaction?
- Define half-life of a reaction.
- If the value of rate constant in a rate law is found to be 2.0 x 10
^{-3}molL^{-1}sec^{-1}what is the order of the reaction. - If the order of the reactant X is ½ and the order of the reactant Y is 3/2 what is the overall order? Write a rate law expression for the reaction.
- Write the differential rate expression for the reaction
- A + B C
- 2A + 3B 2C

- For the reaction A
_{2}+ 3B_{2}2AB_{3}the rate of reaction measured as was found to be 2.4 x 10^{-4 }mol L^{-1}sec^{-1}. Calculate the rate of reaction expressed in terms of A_{2}and B_{2}(Ans. 1.2 10^{-4 }mol L^{-1}sec^{-1}, 3.610^{-4 }mol L^{-1}sec^{-1}) - Ammonia and oxygen reacts at high temperatures as
- 4NH
_{3 }+ 5O_{2}4NO + 6H_{2}O - From the above reaction the following observations were made the concentration of NO increases by 1.08 x 10
^{-2}molL^{-1}in 3 seconds. Calculate the

- 4NH

i. rate of reaction [3.6 x 10^{-3} molL^{-1} sec^{-1}]

ii. rate of disappearance of ammonia [3.6 x 10^{-3} molL^{-1}sec^{-1}]

iii. the rate of formation of water [5.4 10^{-3} molL^{-1} sec^{-1}]

- If the concentration of a reactant is doubled the rate of the reaction increases 9 by times what is the order of the reaction?

- A first order reaction is found to have a rate constant k = 7.39 x 10
^{-5}sec^{-1}. Find the half-life of this reaction. [Ans: 9.38x 10^{3}] -
For a first order reaction it takes 5 minutes for the initial concentration of 0.6molL

^{-1}to become 0.4molL^{-1}. How long will it take for the initial concentration to become 0.3 mol L^{–}[Ans 8.55min]

Answers to practice coming soon