MCQs of Chemical Kinetics

Chemical Kinetics MCQs

MCQs of Chemical Kinetics

Showing 171 to 180 out of 228 Questions

171.

Which of the following is pseudo first order reaction ?

(a)	Decomposition of hydrogen peroxide.
(b)	Decomposition of HI on the surface of Au.
(c)	Hydrolysis of sucrose into glucose and fructose in presence of acid.
(d)	Hydrolysis of methyl acetate in presence of dilute NaOH.

172.

The unit of K for pseudo first order reaction is _____ .

(a)	mol^-1 lit minute^-1
(b)	mol lit^-1 minute^-1
(c)	mol^-2 lit² minute^-1
(d)	minute^-1

173.

Reaction having high order of reaction are rare because _____ .

(a)	there is little possibility of collisions amongst more molecules at the same time
(b)	they have high activation energy
(c)	such reactions have many steps (stages)
(d)	their enthalpy change in very high

174.

Which of the following is a second order reaction ?

(a)	Inversion of sucrose
(b)	Acidic hydrolysis of ester
(c)	Decomposition of HI on Au-surface
(d)	$H_{2} + I_{2} \to 2 HI$

175.

Which of the following statements is true regarding molecularity and order of reaction ?

(a)	Molecularity cannot be defined for the reactions occurring in more than one step.
(b)	Order of reaction can be determined from stoichiometry of the reaction.
(c)	For the complex reaction, the fastest step decides order of the reaction.
(d)	The order of the reaction for trimolecular reaction is always 2.

176.

What is the realation between half life period and initial concentration for a reaction of (n - 1) order ?

(a)	$t_{\frac{1}{2}} \propto {[R]}_{0}$
(b)	$t_{\frac{1}{2}} \propto {[R]}_{0}^{2 - n}$
(c)	$t_{\frac{1}{2}} \propto {[R]}_{0}^{n + 1}$
(d)	$t_{\frac{1}{2}} \propto {[R]}_{0}^{n - 2}$

177.

For which of the following reactions, Ostwald's isolation method is useful for determination of order of the reaction ?

(a)	$H_{2} O_{2 (l)} \to H_{2} O_{(l)} + \frac{1}{2} O_{2 (g)}$
(b)	$5 {Br}_{(aq)}^{- 1} + {BrO}_{3 (aq)}^{-} + 6 H_{(aq)}^{+} \to 3 {Br}_{2 (aq)} + 3 H_{2} O_{(l)}$
(c)	All the three given options
(d)	$N_{2} O_{5 (g)} \to 2 {NO}_{2 (g)} + \frac{1}{2} O_{2 (g)}$

178.

The half life period of the reaction

H_{2} + I_{2} \to 2 HI

is proportional to _____ .

(a)	the square of the initial concentration
(b)	inverse of initial concentration
(c)	independent of initial concentration
(d)	initial concentration

179.

If temperature of reaction increased by 10°, rate becomes nearly double, if the temperature of a reaction is increased from 10° to 90°, how many times the reaction rate will increase ?

(a)	256
(b)	128
(c)	512
(d)	64

180.

If according to Arrhenius equation,

$K = 4.5 \times 10^{11} e^{\frac{- 28000}{T}}$

What is the value of E_a in Joules ?

(a)	232.8 kJ
(b)	$28000 \times 4.5 \times 10^{11} kJ$
(c)	$\frac{4.5 \times 10^{11}}{28000} kJ$
(d)	$\frac{28000 \times 8.314}{4.5 \times 10^{11}} kJ$

Showing 171 to 180 out of 228 Questions