Q.1
Activation energy of a chemical reaction can be determined by ...[ CBSE 1997]
  • a) evaluating rate constant at standard temperature
  • b) evaluating velocities of reaction at two different temperature
  • c) evaluating rate constants at two different temperatures
  • d) changing concentration of reactants
Q.2
Rate of gaseous reaction is given by the expression Rate = k[A][B] If the volume of reaction vessel is suddenly reduced to one fourth of initial volume, the reaction rate relating to original rate will be
  • a) 1/10
  • b) 1/8
  • c) 8
  • d) 16
Q.3
The rate of reaction that does not involve gases, is not dependent on
  • a) pressure
  • b) catalyst
  • c) concentration
  • d) temperature
Q.4
If the rate of the reaction is equal to the rate constant, the order of the reaction is ...[ CBSE 2003]
  • a) 2
  • b) 3
  • c) 0
  • d) 1
Q.5
In general, with very 10°C rise in temperature, the rate of reaction becomes approximately ...
  • a) ten times
  • b) double
  • c) half
  • d) one tenth
Q.6
Assertion The rate of reaction increases generally to 2 times for every 10°C rise temperature Reason Increase in temperature increases the collision frequency
  • a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
  • b) The Assertion and Reason are true but Reason is not correct explanation of Assertion
  • c) Assertion is true but, Reason is false
  • d) Assertion is false but, Reason is true
Q.7
A first order reaction is 50% completed in 30 minutes at 27°C. Its rate constant is ...[ BHU 1998]
  • a) 2.31 ×10⁻² min-1
  • b) 3.21 ×10⁻⁵ min-1
  • c) 4.75 ×10⁻² min-1
  • d) 1.33 ×10⁻³ min-1
Q.8
In a chemical reaction two reactants take part. The rate of reaction is directly proportional to the concentration of one of them and inversely proportional to the concentration of the other. the order of reaction is ...[ CPMT 2003]
  • a) zero
  • b) 1
  • c) 2
  • d) 4
Q.9
Assertion The molecularity of the reaction, H2+Br2 → 2HBr is 2 Reason The order of this reaction is 3/2
  • a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
  • b) The Assertion and Reason are true but Reason is not correct explanation of Assertion
  • c) Assertion is true but, Reason is false
  • d) Assertion is false but, Reason is true
Q.10
If the rate of reaction between A and B is given by rate = k[A][B]2, then the reaction is
  • a) First order in A
  • b) Second order in B
  • c) Third order overall
  • d) All are correct
Q.11
The rate constant of first order reaction is 10-2 min-the half-life period of reaction is .... [AFMC 2001]
  • a) 693 min
  • b) 69.3 min
  • c) 6.93 min
  • d) 0.693 min
Q.12
Half-life of reaction is halved as the initial concentration of the reactant is doubled. The order of reaction is
  • a) 0.5
  • b) 1.0
  • c) 2.0
  • d) 0
Q.13
Catalyst increases rate of reaction by ...[ CPMT 1994]
  • a) decreasing equilibrium constant
  • b) decreasing threshold energy
  • c) decreasing activation energy
  • d) none of the above
Q.14
For a chemical reaction, A → E, it is found that rate of reaction is doubled when the concentration of A is increased four times. The order of the reaction is
  • a) zero
  • b) 1/2
  • c) 1
  • d) 2
Q.15
DDT on exposure to water decomposes (t1/2 = 10 years). How much time it will take for decomposition to 99% according to first order kinetics?
  • a) 50 yrs
  • b) 70 yrs
  • c) 500 yrs
  • d) 700 yrs
Q.16
Which of the following statements for the order of reaction is incorrect? [ CBSE 2011]
  • a) Order of reaction is always whole number
  • b) Order can be determined only only experimentally
  • c) Order is not influenced by stoichiometric coefficient of the reactants
  • d) Order of reaction is sum of power to the concentration terms of reactants to express the rate of reaction
Q.17
A zero order reaction is one
  • a) in which reactants do not react
  • b) in which one of the reactants is in large excess
  • c) whose rate is uniform and not affected by time
  • d) whose rate increases with time
Q.18
Positive catalyst lower the activation energy of the reaction where as heat of reaction remains same Reason Heat of reaction is equal to the difference between activation energies for forward and the backward reactions
  • a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
  • b) The Assertion and Reason are true but Reason is not correct explanation of Assertion
  • c) Assertion is true but, Reason is false
  • d) Assertion is false but, Reason is true
Q.19
The rate at which a substance reacts depends upon its
  • a) atomic mass
  • b) equivalent mass
  • c) molecular mass
  • d) active mass
Q.20
The reaction A → B follows first order kinetics. The time taken for 0.8 mol of A to produce 0.6mol of B is 1 hour. What is the time taken for conversion of 0.9 mol of A to produce 0.675 mol of B ..[ CBSE 2003]
  • a) 0.25 hour
  • b) 2 hours
  • c) 1 hour
  • d) 0.5 hour
Q.21
Number of molecules of a substance present in 1 litre volume is known as [ MPPMT 1993]
  • a) molar concentration
  • b) active mass
  • c) activity
  • d) none of the above
Q.22
The half-life of a substance in a first order reaction is 15 minutes. the rate constant is ...[ AIIMS 2002]
  • a) 2.46 ×102 min-1
  • b) 4.62 ×10⁻² min-1
  • c) 3 ×10⁻⁵ min-1
  • d) 3×10⁻⁹ min-1
Q.23
Number of molecules must overcome an energy barrier is given by
  • a) A
  • b) k
  • c) e-Ea/RT
  • d) Ea
Q.24
Among which of the following factor the specific reaction rate of a first order reaction depends on ...[ AFMC 2003]
  • a) temperature
  • b) concentration of reactant
  • c) pressure
  • d) volume
Q.25
According to the law of mass action, rate of a chemical reaction is proportional to ..[ AFMC 2005]
  • a) concentration of reactants
  • b) molar concentration of reactants
  • c) concentration of products
  • d) molar concentration of products
Q.26
The hypothetical reaction A2 + B2 → 2AB, follows the following mechanism A2 ⇄ A +A (fast) A + B2 → AB + B (slow) A + B → AB (fast) The order of the overall reaction is ....[Pb.PMT 1991]
  • a) zero
  • b) 1
  • c) 2
  • d) 3/2
Q.27
If the concentration of reactants is increased by a factor (x), the rate constnat k becomes:
  • a) ek/x
  • b) k/x
  • c) k
  • d) kx
Q.28
In a reaction, 2A2 + B2 → 2A2B, the reactant A will disappear at ...
  • a) half the rate that B will decrease
  • b) the same rate that B will decrease
  • c) double the rate that A2B will form
  • d) twice the rate that B will decrease
Q.29
Assertion The order of the reaction CH3COOC2H5 + H2O ⇒ CH3COOH + C2H5OH is 2 Reason The molecularity of this reaction is 2
  • a) Both Assertion and Reason are true and Reason is the correct explanation of Assertion
  • b) The Assertion and Reason are true but Reason is not correct explanation of Assertion
  • c) Assertion is true but, Reason is false
  • d) Assertion is false but, Reason is true
Q.30
The activation energy of a reaction is zero. The rate constant of the reaction
  • a) increases with increase of temperature
  • b) decreases with decrease of temperature
  • c) decreases with increase of temperature
  • d) is nearly independent of temperature
0 h : 0 m : 1 s