Entry Test Preparation 2015, Chemistry BOOK 1 Chapter # 11, MCQS With Answer Keys

Entry Test Preparation 2015, Chemistry BOOK 1

CHAPTER #11

REACTION KINETICS

1.         The rate of reaction

            (a) increases as the reaction proceeds            

(b) decreases as the reaction proceeds

            (c) remains the same as the reaction proceeds

(d) may decrease or increase

2.         With increase of 10^oC the rate of reaction doubles. This increase in the rate of reaction is due to.

            (a) decrease in activation energy of reaction.

            (b) decrease in the number of collisions b/w reactants molecules

            (c) increase in activation energy of reactants.

            (d) increase in number of effective collisions

3.         The rate of reaction between two specific time intervals is called.

            (a) instantaneous rate (b) average rate           (c) specific rate            (d) ordinary rate

4.         The sum of the exponents of the conc. Terms in the rate equation is called.

            (a) rate of reaction       (b) order of reaction    (c) specific rate constant  (d) average rate

5.         Photochemical reaction usually has order.

            (a) one                         (b) zero                        (c) two                         (d) three

6.         When the rate of reaction is entirely independent of the conc. Of reactants molecule then order of reaction is.

            (a) Zero                       (b) first                        (c) second                    (d) third

7.         When a reaction occurs in many steps then the slowest step is called.

            (a) main step                                                    (b) enthalpy determining step.           

(c) mechanism determining step                     (d) rate determining step

8.         Spectrophotometry is applied for rate determination when.

            (a) reactants or  product absorb U.V. & I.R. light.

            (b) reaction involve ion

            (c) reaction involve change in volume

            (d) none of above

9.         The unit of rate constant for 2^nd order reaction will be:

            (a) moldm^-3s^-1        (b) mol^-1L^-1s^-1             (c)  s^-1           (d) mol L^-1

10.       The unit of slope in Arrhenius equation is:

            (a) Joule           (b) Pascal         (c) kelvin         (d) No unit

11.       The rate equation for a reaction 2A + B  à  products is rate = k [A]^2/3 [B]^1/3

            (a) Zero           (b) 1                 (c) 1/3              (d) 2/3

12.       Optical rotation method is used when

            (a) Reactions involving absorption of I.R or U.V.     (b) Reactions involving ions

            (c) Reactions involving volume change                      (d) Change of optical activity

13.       In the hydrolysis of CH₃COOC₂H₅ the acid produce act as:

            (a) inhibitor                 (b) catalyst                  (c) auto catalyst           (d) none of above

14.       The factors which affect rate of reaction.

            (a) nature of reactants             (b) surface area            (c) light                        (d) all of above

15.       Arrehenius equation describe the effect of.

            (a) temperature on rate of reaction                  (b) volume on rate of reaction            

(c) pressure on rate of reaction                        (d) all of above

16.       The reaction rate may be measure by.

            (a) physical method     (b) Chemical method (c) Both a & b             (d) None

17.       By the use of catalysis the energy of activation is.

            (a) Decreased              (b) Increased               (c) Not affected          (d) None

18.       If a reactant or product of a reaction absorbs radiation, then physical method for determining the rate of reaction is.

            (a) Spectrometry                                             (b) Refractrometry

(c) Conductivity measurement                        (d) Optical method

19.       If there is volume change during a reaction, then rate of this reaction is determined by.

            (a) Dilatometric method                                  (b) Spectrometry

            (c) Conductivity method                                (d) Optical rotation method

20.       In the hydrolysis of ethyl acetate, the progress of reaction is determined by measuring the concentration of CH₃COOH at definite time intervals by.

            (a) Measuring PH                                            (b) Measuring density            

(c) Titration against standard NaOH           (d) Titration against standard KMnO₄ solution

21.       For chemical reaction to take place the particles must have sufficient energy for the effective collision, the energy is called.

            (a) Average energy      (b) Activation energy (c) Potential energy     (d) Collision energy

22.       Reactant reach the potential energy hill to form the products. This potential energy hill is called.

            (a) Activated complex                                    (b) Average energy

            (c) Instant aqueous energy state                     (d) Ionization energy

23.       The reaction with zero activation energy will occur.

            (a) Rapidly      (b) Very slowly           (c) Moderately            (d) Without products

24.       When we perform the same reaction by taking two different initial concentrations of a reactant for a second order reaction, then.

            (a) Reaction becomes exothermic                   (b) Energy of activation is different

            (c) Mechanism of reaction is changed            (d) Half life period is changed

25.       Half life period of a reaction is inversely proportional to the initial concentration of the reactant, then order of reaction is.

            (a) Third order             (b) Second order         (c) First order              (d) Zero order

26.       Al foil reacts moderately with NaOH on warming producing H₂ gas but this reaction is rapid of powered Al treated with even cold NaOH it is due to.

            (a) Increased surface area of reactants            (b) Le-Chatliers principle       

            c) Common ion effect                                     (d) Temperature difference

27.       Which statement about Arrhenius equation is incorrect.

            (a) Factor A called Arrhenius constant depend upon collision frequency of reactants.

            (b) Rate of reaction increase by increasing temperature.

            (c) Rate constant k is increased

            (d) Activation energy is decreased by rise in temperature.

28.       A catalyst increases the rate of chemical reaction but remain unchanged because.

            (a) It increase the temperature                        (b) It increases the surface area

            (c) It increases the rate constant                     (d) It decreases the energy of activation

29.       Catalysis in which catalyst and reactants are in the same phase is called as:

            (a) Homogeneous catalysis                             (b) Heterogeneous catalysis

            (c) Both of the above                                      (d) None of the above

30.       Hydrogenation of vegetable oil is accelerated by Ni. The Activity of Ni is increased by a promoter or activator which is.

            (a) Na and K               (b) Na and Hg                         (c) Hg and Zn             (d) Cu and Te

31.       Complex protein molecules which catalyses the organic reaction in the living cells are called as:

            (a) Living organism     (b) Enzymes                (c) Viruses                   (d) Bacteria

32.       The catalytic activity of enzymes is greatly enhanced by.

            (a) Temperature                                               (b) Increasing PH       

(c) Light                                                          (d) Presence of co-enzyme or activator

33.       Which statement about Arrhenius equation is incorrect?

            (a) Rate of reaction increase with increasing temperature

            (b) Activation energy decreases by rise in temperature

            (c) K is rate constant

            (d) A is Arrhenius constant depends upon collision frequency

34.       The value of activation energy from graph is:

            (a) Slope x 2.303 R     (b) 1/ Slope                  (c) Slope                      (d) Slope x R

35.       Which of the following statement about catalyst is true?

            (a) Always decreases activation energy          (b) Always increases rate of reaction

            (c) Both (a) and (b)                                         (d) None

36.       Metals which easily react with acid should fulfill which of the following statements?

            (a) Less oxidation potential as compare to hydrogen            

(b) More oxidation potential as compare to hydrogen

(c) Less reduction potential as compare to hydrogen            

(d) Both (b) and (c)

37.       Which of the following reactions is not feasible according to the electrochemical series?

            (a) 2NaCl + K 2KCl + 2Na                       (b) 2KF + Cl₂  2KCl + F₂

            (c) 2KBr + Cl₂  2KCl + Br₂                       (d) 2Kl + Br₂  2KBr + I₂

38.       When Mg is added in aqueous solution of CuSO4 then colour discharge this indicates that

            (a) Mg is present higher in electrochemical series

            (b) Mg is more reducing agent as compare to Cu

            (c) Mg has less reduction potential as compare to Cu

            (d) All

39.       Which of the following reactions indicates homogeneous catalysis?

            (a) 4HCl + O₂  2H₂O + Cl₂             (b) 2SO₂ + O₂ 2SO₃

            (c) 4NH₃ + 5O₂ 4NO + 6H₂O

            (d) CH₃COOC₂H₅+H₂OCH₃COOH+C₂H₅OH

40.       Which one of the following is heterogeneous catalysis?

            (a) HCOOH H2O+CO      

            (b) H₂C = CH₂ + H₂ CH₃ – CH₃

            (c) CH₃COOC₂H5+H₂O CH₃COOH+C₂H₅OH

            (d) 2KClO₃ 2KCl+3O₂

41.       Which of the following is correct?

            (a) C₂H₅OHC₂H₄+H₂O                       (b) C₂H₅OH CH₃CHO+H₂

            (d) C2H5OH C2H4 + H2O                       (d) None

42.       If for a reaction, half-life period is independent of the concentration of the reactants, then the reaction is:

            (a) 3^rd order                 (b) 2^nd order                 (c) Zero order              (d) None

43.       The unit of rate constant and rate of the following reaction is same:

            (a) 3^rd order                 (b) 2^nd order                 (c) Zero order              (d) 1^st order

44.       The half life period for ₉₂U²³⁵ is:”

(a) 7.1 x 10³ years                                           (b) 7.1 x 10⁸ years      

(c) 7.1 x 10¹⁴ years                                          (d) vary with concentrations of ₉₂U²³⁵

45.       The experimental relationship between a reaction rate and the concentration of reactants is called:

            (a) Order of reaction   (b) Rate law    (c) Activated complex            (d) Molecularity

46.       When the rate of reaction is entirely independent of the concentration of reactant molecules then order of reaction is.

            (a) Zero                       (b) Negative                (c) In fractions            (d) Psendo first order

47.       The order of reaction NO₂+CO NO + CO₂

            (a)Zero                        (b)One                         (c)Two                         (d)Three

48.       In the hydrolysis reaction

            CH₃COOC₂H₅ + H₂O CH₃COOH + C₂H₅OH

            The order of reaction is first order because

(a)    Rate is independent of concentration of water since it is in excess

(b)   Rate is independent of concentration of ester since it is in excess

(c)    Rate depends upon the concentration of acid catalyst added

(d)   Rate = k[CH₃COOC₂H₃]¹² [H₂O]^1/2

(e)     

49.       Value of rate constant is specific for a reaction, the value of k of a reaction changes with

            (a) Time           (b) Temperature           (c) concentration of reactants (d) Order of reaction

50.       The unit of rate constant k is the same as that of the rate of reaction is.

            (a) First order reaction                        (b) Second order reaction

            (c) Third order reaction                       (d) Zero order reaction 

ANSWERS

(reaction kinetics)

1	D	2	C	3	C
4	C	5	C	6	D
7	A	8	C	9	D
10	C	11	B	12	C
13	D	14	B	15	A
16	A	17	B	18	D
19	B	20	A	21	B
22	A	23	B	24	B
25	A	26	D	27	B
28	D	29	D	30	D
31	D	32	B	33	D
34	B	35	D	36	A
37	B	38	C	39	B