Chemical Equilibrium MCQs for MDCAT Practice

Chemistry section, Chemical Equilibrium chapter. Sample questions from past PMC papers.

1. Question 1
   1 mole of CH3COOH and 1 mole of C2H5OH react to produce 2/3 mole of CH3COOC2H5. The equilibrium constant is
   • A.2
   • B.-4
   • C.8
   • D.+4
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
2. Question 2
   In the Haber process for manufacturing of ammonia, Nitrogen is taken from:
   • A.Proteins occurring in living bodies
   • B.Ammonium salts obtained industrially
   • C.Air
   • D.Minerals containing nitrates
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
3. Question 3
   Which one of the following statements is correct about a reaction for which the equilibrium constant is independent of temperature?
   • A.The activation energies for both forward and reverse reactions are zero
   • B.The enthalpy change is zero
   • C.Its rate constants do not vary with temperature
   • D.There are an equal number of moles of reactants and products in it
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
4. Question 4
   Which of the following is an example of an acidic buffer solution?
   • A.0.1 M NaOH + 0.1 M NaCl
   • B.0.1 M NaOH + 0.1 M HCl
   • C.0.1 M NH3 + 0.1 M NH4Cl
   • D.0.1 M NaCl + 0.1 M HNO3
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
5. Question 5
   A + B ⇋ C + D. If at equilibrium A = 0.4 mole/dm3, B = 0.5 mole/dm3, C = 0.3 mole/dm3 and D = 0.8 mole/dm3. Calculate Kc for the reaction 2A + B ⇋ C + D.
   • A.3
   • B.1.5
   • C.2
   • D.None of the above
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
6. Question 6
   Consider the reaction: 2SO2(g) + O2(g) ⇌ 2SO3(g) + heat. If the temperature is decreased, which way will the equilibrium shift?
   • A.Towards the reactants
   • B.towards the products
   • C.no shift will occur
   • D.it depends on the initial concentrations of the reactants and products
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
7. Question 7
   Suppose the following system has reached equilibrium at a certain temperature: N2​O4​(g)→2NO2​(g) Adding N2​O4​ to the system will:
   • A.Start forward reaction
   • B.Start reverse reaction
   • C.Not disturb equilibrium
   • D.Raise the temperature of system
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.
8. Question 8
   A small value of Kc suggest that position of equilibrium
   • A.Is constantly changing
   • B.Lies towards left
   • C.Remains same after adding reactant
   • D.Independent of T
   Sign up free to see the explanation, distractor analysis, and add this to your spaced repetition deck.