Chemistry Question Bank

Half-lives of a first order and a zero order reaction are same. Then the ratio of the initial rates of first order reaction to that of the zero order reaction is (a) 0.693

Hydrolysis of methyl acetate in aqueous solution has been studied by titrating the liberated acetic acid against sodium hydroxide. The concentration of the ester at different times is given below. t/min C/mol L-1 0.85…

The following data were obtained during the first order thermal decomposition of SO₂Cl₂ at a constant volume. 2(g) 2(g) 2(g) SO Cl SO Cl → Experimen t Time/s-1 Total pressure/atm 0.5 0.6 What is the rate of reaction w…

1 mL of ethyl acetate was added to a flask containing 20 mL of N/20 HCl maintained at 25 °C. 2 mL of the reaction mixture were withdrawn at different intervals and titrated with a standard alkali solution. The followi…

From the following data find rate constant of decomposition of H₂O₂ in aqueous solution Time (in minutes) Volume (in cc of KMnO₄) 22.8 13.3 8.25

For the reaction : sunlight H Cl 2HCl →

The initial rates of reaction 3A + 2B + C → Products, at different initial concentrations are given below: Initial rate M s–1 [A]0 , M [B]0 , M [C]0 , M 5.0 × 10–3 0.010 0.005 0.010 5.0 × 10–3 0.010 0.005 0.015 1.0 × …

The hypothetical reaction A B 2AB; → follows the following mechanism Fast A A A, → Slow Fast A B AB B,A B AB. → → The order of the overall reaction is

The reaction of hydrogen and iodine monochloride is given as: H g 2ICl g 2HCl g I g → The reaction is of first order with respect to H₂ (g) and ICl(g), following mechanisms were proposed. Mechanism A: H g 2ICl g 2HCl …

For a certain reaction A → products, the t1/2 as a function of [A]0 is given as below: [A]0 (M) : 0.1 0.025 t1/2 (min) : 100 Which of the following is/are true ?

The first order rate constant for a certain reaction increases from 1.667 × 10–6 s–1 at 727ºC to1.667 × 10–4 s–1 at 1571ºC. The rate constant at 1150ºC, assuming constancy of activation energy over the given temperatu…

Ea and H values of reactions R1, R2, R3 and R4 carried out at the same temperature are as given below: R1 Ea = 40 kJ mol–1, H = – 80 kJ mol–1 R2 Ea = 20 kJ mol–1, H = – 30 kJ mol–1 R3 Ea = 60 kJ mol–1, H = + 40 kJ mol…

The potential energy diagram for a reaction R P → is given below o H of the reaction corresponds to the energy:

An endothermic reaction with high activation energy for the forward reaction is given by the diagram : (a) (b) (c) E E (d)

For a first order reaction A P, the temperature (T) dependent rate constant (k) was found to follow the equation 1 logk 6.0 T . The pre- exponential factor A and the activation energy Ea, respectively are: (a) 1.0 10 …

Assertion (A): The order of a reaction can have fractional value. Reason (R): The order of a reaction cannot be written from balanced equation of a reaction.

Assertion (A): If the activation energy of a reaction is zero, temperature will have no effect on the rate constant. Reason (R): Lower the activation energy, faster is the reaction.

The instantaneous rate of reaction at the beginning of the reaction is

Assertion : If the equation for a reaction is reversed, the equilibrium constant is inverted and if the equation is multiplied by 2, the equilibrium constant is squared. Reason : The numerical value of equilibrium con…

Assertion : For a reaction at equilibrium, the free energy for the reaction is minimum. Reason : The free energy for both reactants and products decreases and become equal.

For the reaction : N (g) O (g) NO(g) If pressure is increased by reducing the volume of the container, then

If for a particular reversible reaction : Kc = 57 at 355ºC and Kc = 69 at 450º, then

For exothermic reaction is Sº < 0, then the sketch of log K vs 1/T may be (a) (b) (c) (d)

If standard heat of dissociation of PCl₅ is 230 cal, then slope of the graph of log k vs 1 T is

Assertion : For PCl₅(g) PCl₃(g) + Cl₂(g). If more Cl₂ is added, the equilibrium will shift in backward direction hence equilibrium constant will decrease. Reason : Addition of inert gas to the equilibrium mixture at c…