Chemistry Chapter 7 Entry Test MCQs
26. The rate of chemical reaction becomes doubles with increase of 10oC in temperature due to:
a. Increase in activation energy of reactants
b. Decrease in energy o activation
c. Increase in the number of effective collisions
d. Decrease in reactant molecules collision
27. In which of the following techniques, rate of reaction is directly related with number of ions
a. dilatometric method
b. Spectrometry
c. Refractrometry
d. Conductometry
28. For the reaction A + H2O → products, find the rate of the reaction when [A] = 0.75 M, k= 0.02.
a. 0.015 s-1
b. 0.077 s-1
c. 0.026 s-1
d. 0.085 s-1
29. On increasing the temperature the rate of reaction increases mainly because
a. Collision frequency increases
b. The activation energy of the reaction increases
c. Nature of reactants is changed
d. The concentration of the reacting molecules increases
30. Radiations are absorbed in
a. Dilatometric method
b. Spectrophotometer method
c. Refractometric method
d. Optical relation method
31. Which of the following will not have a very high rate of reaction?
a. Neutralization reaction
b. Double decomposition reaction
c. Hydrolysis of ester
d. Ionic reactions
Order of Reaction + Methods to determine it
32. For the zeroth-order reaction: A → products, what will happen to the rate of reaction if the concentration A is doubled?
a. The rate will remain the same
b. The rate will be doubled
c. The rate will be quadrupled
d. the rate will be halved
33. The elementary reaction: 2HI → H2 + I2, is an example of a___reaction.
a. Bimolecular
b. Tetramolecular
c. Unimolecular
d. Termolecular
34. 3A → B + C It would be a zero order reaction when:
a. The rate remains unchanged at any concentration of B and C
b. the rate of reaction is proportional to square of concentration of A
c. the rate of reaction doubles if concentration of B is increased to double
d. The rate of reaction remains same at any concentration of A
35. What will be initial rate of a reaction if its constant is 10-3 min-1 and the concentration of reactant is 0.2 mol dm-3?
a. 0.002 moldm-3min-1
b. 0.02 moldm-3min-1
c. 2 mol dm-3 min-1
d. 0.0002 mol dm-3 min-1
36. The rate of a gaseous reaction is given by the expression k[A][B]. If the concentration of reactants is increased four times, the reaction rate relating to original rate will be
a. 1/10
b. 8
c. 16
d. 1/8
37. Which of the following is/are experimentally determined?
a. Molecularity
b. Rate law
c. Rate constant
d. Order
38. Rate = K[A]2[B] for the reaction 2A + B → Product and ‘A’ is present is large excess, then order or reaction is:
a. 3
b. 1
c. 4
d. 2
39. The order of reaction can be measured by:
a. Electrical conductivity method
b. Dilatometric method
c. Absorption of radiation
d. Half life method
40. Hydrolysis of Tertiary butyl bromide has order of reaction
a. First Order
b. Pseudo first order
c. Second order
d. Third order
41. If for a reaction, half-life period is independent of the concentration of the reactants, then the reaction is:
a. Zero order
b. 3rd order
c. 1st order
d. 2nd order
42. The incorrect statement is
a. Formation of H2SO4 by contact process is heterogeneous equilibrium
b. Specific rate constant changes with temperature
c. In zero order reaction the rate is dependent on concentration of reactant
d. Decomposition of nitrogen pentaoxide is first order reaction
43. Some reactions are called pseudo-first order reactions. Because
a. Changing the concentration of one reactant does not change rate of reaction.
b. One of the reactant from two does not take part in reaction.
c. Rate constant is changed due to change in conc. of one reactant.
d. Of large conc. one reactant remains dominant in controlling rate of reaction.
44. Rate of reaction doubles by increasing temperature by 10K. If temperature is increased from 30K to 90K, then rate of reaction will increase
a. 32 times
b. 8 times
c. 64 times
d. 16 times
45. What is the rate law for acid hydrolysis of an ester such as CH3COOC2H5 in aqueous solution?
a. k [CH3COOC2H5] [H2O]
b. k [CH3COOC2H5]
c. k
d. k [CH3COOC2H5]2
46. How many times will the rate of the elementary reaction 3X + Y → X2Y change if the concentration of the substance X is doubled and that of Y is halved?
a. r2= 2r1
b. r2= 4.5r1
c. r2= 4r1
d. r2= 5r1
47. The rate expression of a reaction is “Rate = K [A]2[B ]. What becomes to rate of reaction if ‘A’ and ‘B’ concentration are doubled? Rate of reaction is:
a. Increased six times
b. Doubled
c. Increased eight times
d. Increased four times
48. Which of the following observations is incorrect about the order of a reaction?
a. The stoichiometric coefficient of the reactants doesn’t affect the order
b. Order of a reaction is always a whole number
c. Order of reaction is the sum of power to express the rate of reaction to the concentration terms of the reactants.
d. Order can only be assessed experimentally
49. Order of reaction of 2N2O5 → 2N2O4+O2 is
a. Third order
b. First order
c. Zero-order
d. Second order
50. The reaction between chlorine and nitric oxide to form nitrosyl chloride is shown below. If the reaction rate doubles when the concentration of CI2 is doubled and the rate quadruples when the concentration of NO is doubled, by what factor will the rate increase if both concentrations, NO and Cl, are doubled? Cl2 (g) + 2NO (g) → 2NOCI (g)
a. 12
b. 4
c. 16
d. 8