Chemistry Question Bank

T50 of first -order reaction is 10 min. Starting with 10 mol L–1, rate after 20 min is

A reaction which is of first order w.r.t. reactant A, has a rate constant 6 min–1. If we start with [A] = 0.5 mol L–1, when would [A] reach the value of 0.05 mol L–1

The following data pertains to reaction between A and B : S. No. [A] mol L–1 [B] mol L–1 Rate (mol L–1 time–1) 1 1.0 × 10–2 2.0 × 10–2 2.0 × 10–4 2 2.0 × 10–2 2.0 × 10–2 4.0 × 10–4 3 2.0 × 10–2 4.0 …

For the following reaction: NO2(g) + CO(g) ->NO(g) + CO2(g), the rate law is: Rate = k [NO2]2.If 0.1 mole of gaseous carbon monoxide is added at constant temperature to the reaction mixture which of the following stat…

Select the rate law that corresponds to the data shown for the following reaction A B C -> Expt. (A) (B) Initial rate 0.012 0.035 0.10 0.024 0.070 0.80 0.024 0.035 0.10 0.012 0.070 0.80

With passage of time, the concentration of reactants …A… and rate of reaction …B… . Here A and B are

For the reaction 4 A B C D -> , which of the following statement is not correct ?

The rate of formation of NO2 during the period 600 – 700 s is

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

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.

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): In rate law, unlike in the expression for equilibrium constants, the exponents for concentrations do not necessarily match the stoichiometric coefficients. Reason (R): It is the mechanism and not the ba…

Choose the correct answer out of the following choices. Assertion (A): Most people think diamond is forever. Reason (R): Conversion rate of diamond to graphite is very low.

Collision theory is used to explain how chemical species undergo a reaction. Using this theory and the kinetic molecular model, which of the following does NOT influence the rate of a chemical reaction?

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…

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

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

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 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…

In most cases, for a rise of 10K temperature the rate constant is doubled to tripled. This is due to the reason that (a)collision frequency increases by a factor of 2 to 3. (b)fraction of molecules possessing threshol…

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 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 2…

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 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 ×…

For the reaction : sunlight H Cl 2HCl ->