Chemistry Question Bank

For a reaction pA + qB ⟶ products, the rate law expression is r = k [A]m [B]n then

Which of the following statement is/are correct? (a) A catalyst is used in the rate determining step of a mechanism, but then is formed again in some subsequent step so that there is no change in the concentration of …

Mark the correct statement.

Which of the following statement is correct?

Chemical equilibria are important in numerous … (X) … and …. (Y) … processes. Here, (X) and (Y) refer to

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

Au(s) Au(l) Above equilibrium is favoured at

When a gas “X” is dissolved in water, the heat is evolved. Then solubility of ‘X’ will increase at

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…

Assertion :A catalyst does not influence the value of equilibrium constant. Reason : Catalyst influence the rate of both forward and backward reactions equally.

Assertion : The addition of an inert gas under constant volume condition cause the total pressure of the system to increase. This would thus lower the degree of dissociation of PCl5. Reason : Addition of inert gas at …

Assertion : Addition of an inert gas at constant pressure equilibrium will support the dissociation of PCl5 at the same temperature. Reason : The addition of an inert gas will tend to increase the total pressure.

Assertion : For the reaction g g g g A B C D at the given temperature, there will be no effect by addition of inert gas either at constant pressure or at constant volume. Reason : For the reaction where n = 0,…

Assertion : Kp is equal to Kc for the following reaction: N2(g) + O2(g) 2NO(g) Reason : Kp and Kc are interrelated by the following equation : g n p c K K (RT) ng = Number of gaseous moles of products – Number of g…

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 reversible reaction, Gibbs’ free energy is zero at equilibrium. Reason : As reaction approaches equilibrium, Gibbs’ free energy decreases.

Assertion : If some PCl5(g) containing labelled phosphorus P31 is added to a system with following equilibrium, after sometime the system was found to contain radioactive PCl3. PCl (g) PCl (g) Cl (g) Reason : Chemic…

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.

In a 1.0 L aqueous solution when the reaction (aq) (s) 2 Ag Cu (aq) (s) Cu 2 Ag reaches equilibrium, [Cu2+] = x M and [Ag+] = y M. If the volume of solution is doubled by adding water, then at equilibrium : (a) x …

Variation of log K with 1 T is shown by the following graph. Hº for the reaction will be :

In each of the following, total pressure set-up at equilibrium is assumed to be equal and is one atm with equilibrium constants KP given : I :CaCO3 (s) CaO (s) + CO2 (g), K1 II : NH4HS (s) NH3 (g) + H2S (g), K2 III :…

For the chemical equilibrium, CaCO (s) CaO(s) CO (g) , Hº can be determined from which one of the following graphs ? (a) (b) (c) (d)