Chemistry - Chemical Equilibirium

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Question - 1

Which one of the following is a reversible process ?

  • A mixing of gases by diffusion
  • B dissociation of a  solute in pure solvent
  • C expansion of a gas in vacuum
  • D melting of ice without rise in temprature.

Question - 2

Which one of the following equilibriums moves backward when pressure is applied ?

  • A \(N_{2}(g) + 3H_{2}(g) \rightleftharpoons 2NH_{3}(g)\)
  • B \(N_{2}(g) + O_{2}(g) \rightleftharpoons 2NO(g)\)
  • C \(Water??\rightleftharpoons Ice\)
  • D \(I_{2}(g)\rightleftharpoons I_{2}(S)\)

Question - 3

For reversible reaction in equilibrium, in which one of the following cases less products would be formed ?

  • A temperature is raised (\(\triangle \)H is positive)
  • B temperature is raised (\(\triangle \)H is negative)
  • C pressure is lowered (\(\triangle \)H is negative)
  • D noble gas is added while the pressure remains unchanged.

Question - 4

In the system \(CaF_{2}(S)=Ca^{2+}(aq)+2\overline{F}(g),\) increasing the concentration of \(Ca^{2+}\)(aq) four times will cause the equilibrium concentration of  \(\overline F\) change to

  • A 1/2 times of the initial value
  • B 1/4 times of the initial value
  • C 2 times of the initial value
  • D 4 times of the initial value

Question - 5

\(K_{p}\) for the reaction
​​​​​​​\(A(g)+2B(g)\rightleftharpoons 2C(g)+D(s) \) is

  • A \([C^{2}]\over[A][B^{2}]\)
  • B \([C^{2}]\over[A][B]^{2}\)
  • C \([C^{2}][D]\over[A][B]^{2}\)
  • D \([A][B]^{2}\over[C^{2}][B]\)

Question - 6

Which one of the following reactions has the least tendency to go to completion?

  • A \(2H_{2}(g)+O_{2}(g)\rightleftharpoons 2H_{2}O; \ K=1.7\times10^{27}\)
  • B \(N_{2}(g)+O_{2}(g)\rightleftharpoons 2NO;\ K=5.0\times 10^{-31}\)
  • C \(H_{2}(g)+C1_{2}(g)\rightleftharpoons 2HC1(g); \ K=3.2\times10^{16}\)
  • D \(2NOC1(g)\rightleftharpoons 2NO(g)+C1_{2}(g);\)

Question - 7

What is the unit of \(K_{c}\) for the following equilibria \(2NO(g)+C1_{2}\rightleftharpoons 2NOC1(g)\)

  • A \(mol\ l^{-1}\)
  • B \(l mol^{-1}\)
  • C \(l\ cm^{-1}\)
  • D no units

Question - 8

For the following two equilibria
\(SO_{2}(g)+1/2O_{2}(g)\rightleftharpoons SO_{3}(g); K_{1}\)
\(2SO_{3}(g)\rightleftharpoons 2SO_{2}(g)+O_{2}(g); K_{2}\)

The values of equilibrium constants are related by

  • A \(K_{2}=K_{1}^{2}\)
  • B \(K_{2}+{1\over K^{2}_{1}}\)
  • C \(K_{2}=K_{1}\)
  • D \(K_{2}={1\over K_{1}}\)

Question - 9

In which of the following does the reaction go almost to completion?

  • A \(K_{c}=10^{3}\)
  • B \(K_{c}=10^{2}\)
  • C \(K_{c}=10^{-2}\)
  • D \(K_{c}=10^{-3}\)

Question - 10

Conisider the reaction \(A(g)+B(g)??\rightleftharpoons C(g)+D(g)\)  Which occurs in one step. The specific rate constants are 0.25 and \(5.0\times 10^{13}\) for the forward and reverse reactions respectively.  The value of equilibrium constant would be

  • A \(2.25\times10^{-6}\)
  • B \(5.0\times10^{-5}\)
  • C \(4.0\times10^{2}\)
  • D \(2.0\times10^{4}\)