PHYSICAL CHEMISTRY
DAILY PRACTICE PROBLEM
TARGET–NEET
DPP-1
Chemical Equilibrium
e
1. An example of a reversible reaction is 5. In A + B C. The unit of equilibrium
(1) Pb(NO3)2 (aq)+2NaCI (aq) = PbCI2 (s) + constant is :
2NaNO3(aq) (1) Litre mole–1 (2) Mole litre
(2) AgNO3 (aq) + NaCl (aq) = AgCl (s) + (3) Mole litre –1
(4) No unit
NaNO3 (aq)
(3) 2Na (s) + H2O (I) = 2NaOH (aq) + H2 (g) 6. For the homogeneous reaction :
(4) KNO3 (aq) + NaCl (aq) = KCl (aq) + 4NH3 + 5O2 4NO + 6H2O
the equilibrium constant Kc, has the units of
NaNO3 (aq) (1) Conc.+10
(2) Conc.+1
(3) Conc.–1
2. For the following chemical reaction 2X + Y
(4) It is dimension less
Z, the expression of equilibrium constant
will be 7. CO and Cl2 are allowed to interact in a 500
ml flask to form COCl2 At equilibrium,
X Y XY
2 2
concentrations of CO, Cl2 and COCl2 are
(1) KC (2) KC
Z Z found 0.1, 0.1 and 0.3 gm moles respectively.
The equilibrium constant will be :
(3) K C
Z (4) K C
Z (1) 30 (2) 3
(3) 15 (4) 0.3
X Y XY
2 2
8. The rate at which a substance reacts depends
on its :
3. Consider the imaginary equilibrium : (1) Atomic weight (2) Molecular weight
4A + 5B 4X + 6Y (3) Equivalent weight (4) Active mass
The equilibrium constant Kc has the unit 9. For the reaction :
2 –2 –1 2SO3 2SO2 + O2
(1) Mole litre (2) Litre mole
–1 the equilibrium constant expression is
(3) Mole litre (4) Litre2 mole–2
2 SO 2 O 2
(1) K C
2 SO3
4. In the chemical reaction :
(2) K C
SO2 O2
N2+3H2 2NH3
SO3
at equilibrium point, state whether
SO3
2
(1) Equal volumes of N2 and H2 are reacting (3) KC
SO2 O2
2
(2) Equal masses of N2 and H2 are reacting
SO2 O2
2
(3) The reaction has stopped (4) KC
SO3
2
(4) The same amount of ammonia is formed
as is decomposed into N2 and H2
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10. What is the equilibrium expression for the 18. For the following gaseous reaction H2 + I2
reaction P4(s)+5O2 P4O10(s) ? 2HI , the equilibrium constant
5
(1) KC = 1/ [O2] (1) Kp > Kc (2) Kp < Kc
(2) KC = [P4O10] / 5[P4][O2] (3) Kp = Kc (4) Kp = 1/Kc
[3] KC = [O2]5
(4) KC = [P4O10] / [P4][O2]5 19. For which one of the following reactions Kp =
Kc
11. A reversible chemical reaction having two (1) N2 + 3H2 2NH3
reactants, is in equilibrium. If the (2) N2 + O2 2NO
concentrations of the reactants are doubled (3) PCl5 PCl3 + Cl2
then the equilibrium constant will : (4) 2SO3 2SO2 + O2
(1) Be doubled (2) Be halved
(3) Become one fourth (4) Remain the same
20. In which of the following case Kp is less than
Kc
12. For reaction : PCl3(g) + Cl2(g) PCl5(g)
(1) PCl5 PCl3 + Cl2
the value of Kc at 250º C is 26. The value of
(2) H2 + Cl2 2HCl
Kp at this temperature will be :
(1) 0.60 (2) 0.08 (3) 2SO2 + O2 2SO3
(3) 0.83 (4) 0.46 (4) All of these
13. In which of the following equilibria the value 21. For the reaction
1 Kp
CO g O2 g CO2 g ;
of Kp is less than Kc :
(1) H2 + I2 2HI 2 Kc
(2) N2 + 3H2 2NH3 is equivalent to –
(3) N2 + O2 2NO (1) 1 (2) RT
(4) CO + H2O CO2 + H2 1
(3) (4) (RT)1/2
RT
14. The relation between equilibrium constant Kp
and Kc is – 22. Relationship between, Kp and Kc for gaseous
(1) Kc = Kp (RT)n equilibrium is
(2) Kp = Kc (RT)n (1) Kp = (Kc)n RT (2) Kp = Kc(RT)n
n n
Kc (3) Kc = (Kp) RT (4) Kc = Kp (RT)n
(3) K p k
RT
(4) Kp – Kc = (RT)n 23. For the reaction
CO(g) + Cl2(g) COCl2(g)
15. In which of the following reaction, the value the KP / Kc is equal to:
of Kp will be equal to KC (1) 1.0 (2) RT
(1) H2 + I2 2HI (3) RT (4) 1/RT
(2) PCl5 PCl3 + Cl2
(3) 2NH3 N2 + 3H2 24. For the reaction
(4) 2SO2 + O2 2SO3 2NO2(g) 2NO(g) + O2(g)
(Kc = 1.8 × 10–6 at 184ºC)
16. In which of the following reaction Kp > Kc (R = 0.0831 kJ/(mol.K))
When Kp and Kc are compared at 184ºC it is
(1) N2 + 3H2 2NH3
found that
(2) H2 + I2 2HI (1) Whether Kp is greater than, less than or
(3) PCl3 + Cl2 PCl5 equal to Kc depends upon the total gas
(4) 2SO3 O2 + 2SO2 pressure
(2) Kp = Kc
17. For the reaction (3) Kp is less than Kc
PCl5 (g) PCl3 (g) + Cl2 (g) (4) Kp is greater than Kc
(1) Kp = Kc (2) Kp = Kc (RT)–1
(3) Kp = Kc (RT) (4) Kp = Kc (RT)2
Motion Education, 394 - Rajeev Gandhi Nagar 1800-212-1799 | www.motion.ac.in
25. In any chemical reaction, equilibrium is 30. Chemical equations convey quantitative
supposed to be establish when information on the
(1) Mutual opposite reactions undergo (1) Type of atoms/molecules taking part in
(2) Concentration of reactants and resulting the reaction
products are equal (2) Number of atoms/molecules of the
(3) Velocity of mutual reactions become reactants and products involved in the
equal reaction
(4) The temperature of mutual opposite (3) Relative number of moles of reactants and
reactions become equal products involved in the reaction
(4) Quantity of reactant consumed and
quantity of product formed
26. Which of the following conditions represents
an equilibrium
31. For the system 3A 2B C the expression
(1) Freezing of ice in a open vessel,
for equilibrium constant is
temperature of ice is constant
[3A][2B] [C]
(2) Few drops of water is present along with (1) (2)
air in a balloon, temperature of balloon is C [3A][2B]
3 2
constant [A] [B] [C]
(3) (4)
(3) Water is boiling in an open vessel over [C] [A]3 [B]2
stove, temperature of water is constant
(4) All the statements (1), (2) and (3) are 32. A reversible chemical reaction having two
correct for the equilibrium reactants in equilibrium. If the concentrations
of the reactants are doubled, then the
27. In chemical reaction A B, the system will equilibrium constant will
be known in equilibrium when (1) Also be doubled (2) Be halved
(1) A completely changes to B (3) Become one-fourth (4) Remain the same
(2) 50% of A changes to B
(3) The rate of change of A to B and B to A 33. The equilibrium constant in a reversible
on both the sides are same reaction at a given temperature
(1) Depends on the initial concentration of
(4) Only 10% of A changes to B
the reactants
(2) Depends on the concentration of the
28. A chemical reaction is at equilibrium when
products at equilibrium
(1) Reactants are completely transformed into (3) Does not depend on the initial
products concentrations
(2) The rates of forward and backward (4) It is not characteristic of the reaction
reactions are equal
(3) Formation of products is minimised 34. Pure ammonia is placed in a vessel at
(4) Equal amounts of reactants and products temperature where its dissociation constant
are present () is appreciable. At equilibrium
(1) KP does not change significantly with
29. Chemical equilibrium is dynamic in nature pressure
because (2) does not change with pressure
(1) Equilibrium is maintained rapidly (3) Concentration of NH3 does not change
(2) The concentration of reactants and with pressure
products become same at equilibrium (4) Concentration of H2 is less than that of N2
(3) The concentration of reactants and
products are constant but different
(4) Both forward and backward reactions
occur at all times with same speed
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