Equilibrium CBSE Questions & Answers

Equilibrium

This is Chemistry Class 11 Equilibrium CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
When the rate of evaporation is equal to the rate of condensation, it is called
  • A
    balanced reaction
  • B
    reaction at rest
  • C
    Equilibrium
    Correct
  • D
    stable reaction
2
In the dynamic equilibrium stage, one of the following events take place. Choose the right one.
  • A
    no change in the concentrations of either of the reactants or products
    Correct
  • B
    the concentrations of the products are increased
  • C
    the concentrations of the reactants are decreased
  • D
    rates of the forward reaction is faster
3
the rates of transfer of molecules from ice into water and of reverse transfer from water into ice are equal at atmospheric pressure and 273 K. Both the processes occur simultaneously and at the same rate so that the amount of ice and water remains constant. This process is called
  • A
    Liquid-Gas Equilibrium
  • B
    ionic equilibrium
  • C
    dynamic equilibrium
    Correct
  • D
    Liquid-Vapour Equilibrium
4
\({{\text{H}}_{\text{2}}}{\text{O}}\left( {\text{l}} \right)\) \( \rightleftharpoons \) \({{\text{H}}_{\text{2}}}{\text{O}}\) (vap). This equation best illustrates the
  • A
    ionic equilibrium
  • B
    Solid-gas Equilibrium
  • C
    Liquid-solid Equilibrium
  • D
    Liquid-Vapour Equilibrium
    Correct
5
During the process of transformation from liquid to vapour, the pressure exerted by the water molecules at a given temperature remains constant. This is called
  • A
    Boiling point of water
  • B
    melting point of water
  • C
    vapour pressure of water
    Correct
  • D
    freezing point of water
6
If we place solid iodine in a closed vessel, after sometime the vessel gets filled up with violet vapour. When equilibrium is attained, the intensity of colour will be
  • A
    constant
    Correct
  • B
    increases
  • C
    ecreases
  • D
    no colour at all
7
The boiling point of water at atmospheric pressure
  • A
    \({\text{11}}0^\circ {\text{C}}\)
  • B
    \({\text{95}}^\circ {\text{C}}\)
  • C
    \({\text{1}}00^\circ {\text{C}}\)
    Correct
  • D
    \({\text{9}}0^\circ {\text{C}}\)
8
The mass of a gas dissolved in a given mass of a solvent at any temperature is proportional to the pressure of the gas above the solvent.
  • A
    Haber.s process.
  • B
    Arrhenius
  • C
    Le Chatelier
  • D
    Henry’s law
    Correct
9
When the soda bottle is opened, some of the dissolved carbon dioxide gas escapes because of
  • A
    difference in solubility of carbon dioxide at different pressures.
    Correct
  • B
    to reach a new equilibrium condition required for the higher pressure,
  • C
    some of the undissolved carbon dioxide gas in the soda bottle
  • D
    difference in solubility of carbon dioxide at different temperatures.
10
The dynamic nature of chemical equilibrium can be demonstrated in the synthesis of ammonia by Haber.s process. Choose the appropriate option given below
  • A
    by using hydrogen isotope
  • B
    by using deuterium isotope
    Correct
  • C
    by maintaining high temperature and low pressure
  • D
    by using sulphur isotope
11
At a given temperature equilibrium is possible only in a system which is a
  • A
    open system
  • B
    closed system
    Correct
  • C
    partially closed system
  • D
    partially open system
12
For liquid \( \rightleftharpoons \) vapour equilibrium, at a given temperature, the constant is
  • A
    mass of a gas
  • B
    solubility
  • C
    mass of a solvent
  • D
    vapour pressure
    Correct
13
The aqueous solution of sugar does not conduct electricity. However, when sodium chloride is added to water, it conducts electricity. How will you explain this statement on the basis of ionisation and how is it affected by concentration of sodium chloride?
  • A
    Sugar releases more ions in water and increases conductance
  • B
    NaCl ionises completely in water and increase in concentration of salt increases conductance.
    Correct
  • C
    Both sugar and NaCl ionises partially in water thereby increasing the conductance
  • D
    Both sugar and NaCl ionises completely in water thereby increasing the conductance
14
For dissolution of solids in liquids, at a given temperature, the constant is
  • A
    mass of the solute
  • B
    mass of the solvent
  • C
    solubility
    Correct
  • D
    pressure
15
For dissolution of gases in liquids, the concentration of a gas in liquid is.
  • A
    equal to the pressure of the gas in relation to the liquid
  • B
    proportional to the pressure of the gas over the liquid.
    Correct
  • C
    lower to the pressure of the gas as compared to the liquid
  • D
    proportional to the vapour pressure of the gas