CBSE - Chemical Kinetics

Hydrolysis of an ester follows __________

• Zero Order Kinetics

• Pseudo First Order Kinetics

• First Order Kinetics

• Half-life First order Kinetics

Which among the following is a false statement?

• Rate of zero order reaction is independent of initial concentration of reactant.

• Half life of a third order reaction is inversely proportional to square of initial concentration of the reactant.

• Molecularity of a reaction may be zero or fraction.

• For a first order reaction, t1/2 = 0.693/K
  

Which of the following statements about the catalyst is true?

• A catalyst accelerates the rate of reaction by bringing down the activation energy

• A catalyst makes the reaction feasible by making ∆G more negative.

• A catalyst makes equilibrium constant more favourable for forward reaction

• A catalyst does not participate in reaction mechanism.

For a chemical reaction A→B, it is found that the rate of reaction doubles when the concentration of A is increased four times. The order of reaction is

• Two

• One

• Half

• Zero

The half life of the first order reaction having rate constant K = 1.7 x 10^-5s^-1 is

• 12.1 h

• 9.7 h

• 11.3 h

• 1.8 h

In the formation of S02 by contact process;
2SO₂ + O₂ → 2SO₃, the rate of reaction was measured as −d[O2]/dt = 2.5 × 10^-4 mol L^-1s^-1.
The rate of formation of of Sulfur trioxide will be

• -5.0 × 10^-4 mol L^-1s^-1

• -1.25 × 10^-4 mol L^-1s^-1

• 3.75 × 10^-4 mol L^-1s^-1

• 5.00 × 10^-4 mol L^-1s^-1

For the reaction N₂ + 3H₂ → 2NH₃ if Δ[NH3]/Δt = 2 × 10^-4 mol L^-1s^-1, the value of −Δ[H2]/Δt would be:

• 1 × 10^-4 mol L^-1s^-1

• 3 × 10^-4 mol L^-1s^-1

• 4 × 10^-4 mol L^-1s^-1

• 6 × 10^-4 mol L^-1s^-1

What will be the fraction of molecules having energy equal to or greater than activation energy, Ea?

• K

• A

• Ae^-Ea/Rt

• e^-Ea/Rt

For a reaction P + Q → 2 R + S , the incorrect statement is

• Rate of disappearance of P = Rate of appearance of S

• Rate of disappearance of Q = 2 x Rate of appearance of R

• Rate of disappearance of Q = Rate of disappearance of P

• Rate of disappearance of Q = 1⁄2 x Rate of appearance of R

A first order reaction takes 40 min for 30% decomposition. t_1/2 will be

• 77.7 min

• 52.5 min

• 46.2 min

• 22.7 min