Q.1
Half-life of a first order reaction is 10 min. What % of reaction will be completed in 100 min?
  • a) 25%
  • b) 50%
  • c) 80%
  • d) 99.9%
Q.2
The rate constant for the reaction N2O5(g) → 2NO2(g) + ½ O2(g) is 2.3×10-2 sec-Which equation given below describes the change of [N2O5] with time [N2O5]0 and [N2O5]t? ... [ AIIMS 2004 ]
  • a) [N2O5]0 = [N2O5]tekt
    ch-11_qn-121choice_img_no4.png
  • b) [N2O5]t = [N2O5]0 + kt
  • c) log10[N2O5]t = log10[N2O5]0 - kt
  • d)
Q.3
3A → B + C It would be a zero order reaction when ...[ CBSE 2002]
  • a) the rate of reaction is proportional to square of concentration of A
  • b) the rate of reaction remains same at any concentration of A
  • c) the rate remains unchanged at any concentration of B and C
  • d) the rate of reaction doubles if concentration of B is increased to double
Q.4
A substance reacts with initial concentration of a mol dm-3, according to zero order kinetics. the time it takes for the completion of reaction is : (k=rate constant, r0 initial concentration) [KCET 2006]
  • a) k/R0
  • b) R0/2k
  • c) R0/k
  • d) kR0
Q.5
The rate of reaction depends upon .... [ BHU 2000]
  • a) molar concentration
  • b) atomic mass
  • c) equivalent mass
  • d) none of these
Q.6
At 500K, the half-life period of a gaseous reaction at an initial pressure of 80 kPa is 350 sec. When the pressure is 40 kPa, the half-life period is 175 sec; the order of the reaction is
  • a) zero
  • b) one
  • c) two
  • d) two and half
Q.7
For the reaction 2A+B → 3C + D, which of the following does not express the reaction rate ...[ CBSE 2006]
  • a)
    ch-11_qn-126choice_img_no1.png
  • b)
    ch-11_qn-126choice_img_no2.png
  • c)
    ch-11_qn-126choice_img_no3.png
  • d)
    ch-11_qn-126choice_img_no4.png
Q.8
The rate constant for the hydrolysis reaction of an ester by dilute acid is 0.6931×10-3 s-The time required to change the concentration of eter from 0.04M to 0.01M is
  • a) 6931 sec
  • b) 1000 sec
  • c) 4000 sec
  • d) 2000 sec
Q.9
he rate of reaction between A and B increases by a factor of 100, when the concentration of A is increased 10 folds. The order of reaction with respect to A is ...
  • a) 2
  • b) 1
  • c) zero
  • d) 10
Q.10
The decay constant of 6C14 is 2.31 ×10-4 year-Its half-life is ...[ BHU 2000]
  • a) 2×103 yrs
  • b) 2.5×103 yrs
  • c) 3×103 yrs
  • d) 3.5×103 yrs
Q.11
The activation energy of exothermic reaction A → B is 80kJmol-The heat of reaction is 200kJmol-The activation energy for the reaction B →A (in kJ/mol) will be
  • a) 40
  • b) 80
  • c) 200
  • d) 280
Q.12
Activation energy of the reaction is ...
  • a) the energy released during the reaction
  • b) the energy evolved when activated complex is formed
  • c) minimum amount of energy needed to overcome the potential barrier
  • d) the energy needed to form one mole of the product
Q.13
In the first order reaction, the concentration of reaction is reduced to 25% in one hour. The half life period of the reaction is ...[ AFMC 2005]
  • a) 1/4 hr
  • b) 1/2 hr
  • c) 2 hrs
  • d) 4 hrs
Q.14
For the reaction 2N2O5 → 4NO2 + O2 rate and rate constant are 1.02×10-4 Ms-1 and 3.4×10-5 s-1 respectively then concentration of N2O5 at that time will be ...[ CBSE 2001]
  • a) 17.732 M
  • b) 3 M
  • c) 1.02 ×10-4 M
  • d) 3.4 ×105 M
Q.15
The half-life period of a first order reaction is 1 min 40 seconds. Calculate its rate constant.
  • a) 6.93 × 10-3 min-1
  • b) 6.93 × 10-3 sec-1
  • c) 1.93× 10-3 sec
  • d) 1.93× 103 sec
Q.16
ssertion k= Ae-Ea/RT, the Arrhenius equation represents the dependence of rate constant with temperature Reason Plot of log K against 1/T is linear and the activation energy can be calculated with this plot
  • 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.17
For a chemical reaction A → B, the rate of reaction doubles when the concentration of A is increased four times. The order of reaction for A is ...[ BHU 1995]
  • a) zero
  • b) half
  • c) one
  • d) two
Q.18
For the reaction N2O5(g) → 2NO2(g) + ½O2(g), the value of rate of disappearance of N2O5 is given as 6.25×10-3 mol L-1s-The rate of formation of NO2 and O2 is given retrospectively as ...[ CBSE 2010]
  • a) 6.25×10-3 mol L-1s-1 and 6.25×10-3 mol L-1s-1
  • b) 1.25×10-2 mol L-1s-1 and 3.125×10-3 mol L-1s-1
  • c) 6.25×10-3 mol L-1s-1 and 3.125×10-3 mol L-1s-1
  • d) 1.25×10-2 mol L-1s-1 and 6.25×10-3 mol L-1s-1
Q.19
Assertion Order can be different from molecularity of a reaction Reason Slow step is the rate determining step and may involve lesser number of reactants
  • 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.20
3A → 2B, rate of reaction is equals to ...[ CBSE 2002]
  • a)
    ch-11_qn-140choice_img_no1.png
  • b)
    ch-11_qn-140choice_img_no2.png
  • c)
    ch-11_qn-140choice_img_no3.png
  • d)
    ch-11_qn-140choice_img_no4.png
Q.21
The activation energy for a simple chemical reaction A → B is Ea, in forward direction. The activation energy for reverse reaction ...[ CBSE 2003]
  • a) can be less than or more than Ea
  • b) if always double of Ea
  • c) is negative of Ea
  • d) is always less than Ea
Q.22
The rate of a chemical reaction
  • a) increases as the reaction proceeds
  • b) decreases as the reaction proceeds
  • c) may increases or decreases during the reaction
  • d) remains constant as the reaction proceeds
Q.23
In a first order reaction A → P, the ratio of R0/R was found to be 8 after 60 minutes. If concentration is 0.1M, then the rate of reaction in moles of A reacted per minute is ...[ AIIMS 1996]
  • a) 2.226×10-3 mol litre-1 min-1
  • b) 3.466×10-3 mol litre-1 min-1
  • c) 4.455×10-3 mol litre-1 min-1
  • d) 5.532×10-3 mol litre-1 min-1
Q.24
The specific rate constant of a first order reaction depends on ...[ AFMC 2001]
  • a) time
  • b) temperature
  • c) concentration of product
  • d) concentration of the reactants
Q.25
If a first order reaction takes 32 minutes for 80% completion, then time required for 50% completion is ...[ AMU 2006]
  • a) 1.386 min
  • b) 13.86 min
  • c) 8 min
  • d) 4 min
Q.26
For which of the following, the units of rate and rate constant of the reaction are identical?
  • a) zero order
  • b) first order
  • c) second order
  • d) third order
Q.27
According to the collision theory of reation rates, the rate of reaction increases with temperature due to
  • a) decrease in the activation energy
  • b) greater number of collisions
  • c) higher velocity of reacting ,molecules
  • d) greater number of molecules having the activation energy
Q.28
Activation energy (Ea) and rate constant (k1 and k2) of a chemical reaction at two different temperatures (T1 and T2) are related by ...[ AIPMT 2012]
  • a)
    ch-11_qn-148choice_img_no1.png
  • b)
    ch-11_qn-148choice_img_no2.png
  • c)
    ch-11_qn-148choice_img_no3.png
  • d)
    ch-11_qn-148choice_img_no4.png
Q.29
A substance undergoes first order decomposition. The decomposition follows two parallel first order reactions as, k1 = 1.26×10-4 sec-1, k2 = 3.8 ×10-5 sec-1 The percentage distribution of B and C are ...[ Kerala PMT 2004]
ch-11_que_no-149_img_no1.png
  • a) 75% B and 25% C
  • b) 80% B and 20% C
  • c) 60% B nad 40% C
  • d) 90% and 10% C
Q.30
Rate of reaction for following reaction is 3×10-3 mol litre-1 min-What is the value of -d[B]/dt A(g) +3B(g) → 2C(g)
  • a) 3×10-3
  • b) 9×10-3
  • c) 10-3
  • d) 1.5×10-3
0 h : 0 m : 1 s