JEE- Main model

1.) If rate of formation of O₂ is 16g/hr, then rate of decomposition of N₂O₅ and rate of formation of NO₂

     respectively is         

     a) Cannot be calculated without knowing rate constant

     b) 108g/hr, 92g/hr

     c) 32g/hr, 64g/hr

     d) 54g/hr, 46g/hr        

2.) For producing the effective collisions, the colliding molecules must posses

     a) A certain minimum amount of energy

     b) Energy equal to or greater than threshold energy

     c) Proper geometry

     d) Threshold energy and proper orientation

3) The chemical reaction 2O₃ → 3O₂ proceeds as follows:

   O₃ ↔O₂ + O  (fast)

   O + O₃ →2O₃  (slow)

   The rate law expression should be:

   a) r = k[O₃]²

   b) r = k[O₃]²[O₂]^-1

   c) r = k[O₃][O₂]

   d) r = k[O₃]^-1[O₂]²

4) The decomposition of 2N₂O₅→2N₂O₄ + O₂ is at 200⁰C. If the initial pressure is 114mm 

    and after 25min of the reaction the total pressure of reaction mixture is 133mm.

    Calculate the average rate of the reaction in (i) atm m^-1  (ii) mol lit^-1s^-1 respectively

   a) 0.002, 8.58×10^-7

   b) 0.001, 8.58×10^-7

   c) 0.002, 8.58×10^-4

   d) 0.001, 8.58×10^-3

5) The activation energy can be lowered by:

    a) Increasing temperature

    b) Lowering temperature

    c) Adding a catalyst

    d) Removing the products

6) For the reaction  N₂O₅ → 2NO₂ + ⅟₂O₂ ,

    Given     d/dt[N₂O₅] = R₁[N₂O₅]

    d/dt[NO₂] = R₂[N₂O₅],  d/dt[O₂] = R₃[N₂O₅]

   The relation between R₁, R₂ and R₃ is

   a) 2R₁= R₂=4R₃

   b) R₁=R₂=R₃

   c) 2R₁=4R₂=R₃

   d) R₁=4R₂=R₃

7) Molecularity of reaction can be known from

    a) The stoichiometric equation

    b) The mechanism of the reaction

    c) The order of the reaction

    d) The energy of activation of reaction

8) A reaction obeys zero order. The time required to decompose 50g out of 100g of the

     reactant A is 10  minute. Calculate the time required when half of the reactant A is 

    decomposed if its initial mass is 200g.

    a) 5 min

    b) 10 min

    c) 15 min

    d) 20 min

9) For reaction A→B the rate law is, rate=K[A]. Which of the following statement is incorrect?

    a) The reaction follows first order kinetics

    b) The t_⅟2 of reaction depends upon initial concentration of reactants

    c) K is constant for the reaction at a constant temperature

    d) The rate law provides a simple way of predicting the concentration of reactants 

        and products at any time after the start of the reaction.

10) The rate constant, the activation energy and the Arrhenius parameter of a chemical reaction

       at 25⁰ are 3.0×10^-4, 104.4kJ mol^-1 and 6.0×10¹⁴s^-1 respectively.

       The value of rate constant at

       T→∞ is

    a) 2.0×10¹⁸s^-1

    b) 6.0×10¹⁴s^-1

    c) Infinity

    d) 3.6×10³⁰s^-1

^{Answers- 1) b      2) d      3) b      4) a       5) c      6) a       7) b       8) d       9) b      10) b}

^{SOLUTION WILL BE UPLOADED SOON-}