CBSE Class 12 · 2022 · Chemical KineticsShort Answer

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Answer the following questions (any two):
a) Identify the order of a reaction from the following unit of its rate constant: L mol

^{- 1}

^{- 1}

.
b) The conversion of molecules A to B follows second order kinetics. If the concentration of A is increased to three times, how will it affect the rate of formation of B?
c) Write the expression of the integrated rate equation for a zero order reaction.

Answer: (a) Second order. (b) Rate becomes 9 times. (c) [A] = [A]₀ − kt.

Solution

(a) L mol

^{- 1}

^{- 1}

= (mol L

^{- 1}

)

^{- 1}

^{- 1}

⟹ order = 2.
(b) Rate

= k [A]^{2}

; with

[A] \to 3 [A]

rate \to k (3 [A])^{2} = 9 k [A]^{2}

The rate of formation of B becomes nine times.
(c) For zero order:

[A] = [A]_{0} - k t

CBSE Class 12 Board · 2022 · Subjective

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