Chemistry Question Bank

Activation energy (Ea) and rate constants (k1 and k2) of a chemical reaction at two different temperatures (T1 and T2) are related by: (AIPMT 2012) (a) ln a E k k R T T (b) ln a E k k R T T (c) ln a E …

Half-life of a reaction is found to be inversely proportional to the cube of initial concentration. The order of reaction is (AFMC 2012)

The rate of the reaction 2N2O5 -> 4NO2 + O2 can be written in three ways: d N O k N O dt ' d NO k N O dt '' d O k N O dt The relationship between k and k' and between k and k" are; (AIPMT 2011 M)

Which one of the following statements for the order of a reaction is incorrect? (AIPMT 2011)

The unit of rate constant for a zero-order reaction is. (AIPMT 2011 M)

The half-life of a substance in a certain enzyme- catalysed reaction is 138 s. The time required for the concentration of the substance to fall from 1.28 mg L– 1 to 0.04 mg L–1 is (AIPMT 2011)

The rate law for the reaction, xA yB mP nQ -> is rate = . c d k A B What is the total order of the reaction? (Kerala CEE 2011)

For the reaction [N2O5(g) -> 2NO2(g) + 1/2 O2(g)] the value of rate of disappearance of N2O5 is given as 6.25 × l0–3 mol L–1 s–1 The rate of formation of NO2 and O2 is given respectively as: (AIPMT 2010)

The rate of the reaction g g g NO Cl NOCl is given by the rate equation rate = k [NO]2 [Cl2]. The value of the rate constant can be increased by: (AIPMT 2010)

During the kinetic study of the reaction, 2A B C D -> , following results were obtained: Run [A]/mol L–1 [B]/mol L–1 Initial rate of formation of D/mol L–1 min–1 I 0.1 0.1 6.0 10 x II 0.3 0.2 7.2 10 x III 0.3 0.4 2.…

For an endothermic reaction, energy of activation is Ea and enthalpy of reaction of H (both of these in kJ/mol). Minimum value of Ea will be. (AIPMT 2010)

For the reaction, N2 + 3H2 -> 2NH3, d NH dt = 2 x 10–4 mol L–1 s–1, the value of d H dt would be: (AIPMT 2009)

For a hypothetical reaction, R -> products; rate k R . The negative sign used in the rate expression indicates

Half life period of a first-order reaction is 1386 seconds. The specific rate constant of the reaction is: (AIPMT 2009) (a) 0.5 10 s x (b) 0.5 10 s x (c) 5.0 10 s x (d) 5.0 10 s x

rate = k [A]1 [B]2

For the reaction A + B -> products, it is observed that: (1) On doubling the initial concentration of A only, the rate of reaction is also doubled and (2) On doubling the initial concentrations of both A and B, there …

The bromination of acetone that occurs in acid solution is represented by this equation. CH COCH aq Br aq CH COCH Br aq H aq Br aq -> These kinetic data were obtained for given reaction concentrations. …

The rate constants k1 and k2 for two different reactions are 1016. 2000/T e and 1015. 1000/T e , respectively. The temperature at which k1 = k2 is: (AIPMT 2008)

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

In a first-order reaction A B -> , if k is rate constant and initial concentration of the reactant A is 0.5 M, then the half-life is. (AIPMT 2007)

If 60% of a first order reaction was completed in 60 minutes, 50% of the same reaction would be completed in approximately. (AIPMT 2007)

According to collision theory of reaction rates, the rate of reaction depends

The rates of reactions increase with increase of temperature because

Which of the following is a drawback of collision theory? a) Proper orientation b) High activation energy c) Hard spheres d) Have energy equal to or greater than the threshold energy

What is the rate of reaction for a bimolecular elementary reaction?