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What is the effect of adding an inert gas(say He or N₂):
(i) at constant volume and
(ii) at the constant pressure on the following equilibrium:

$PCl subscript 5 left parenthesis straight g right parenthesis space space rightwards harpoon over leftwards harpoon space space space space PCl subscript 3 left parenthesis straight g right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis$

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Short Answer Type

102. Does the number of moles of reaction products increase, decrease or remain the same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?

left parenthesis straight a right parenthesis space PCl subscript 5 left parenthesis straight g right parenthesis space space space rightwards harpoon over leftwards harpoon space space space space PCl subscript 3 left parenthesis straight g right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis left parenthesis straight b right parenthesis space CaO left parenthesis straight s right parenthesis space plus space CO subscript 2 left parenthesis straight g right parenthesis space space space rightwards harpoon over leftwards harpoon space space space space CaCO subscript 3 left parenthesis straight s right parenthesis left parenthesis straight c right parenthesis space 3 Fe left parenthesis straight s right parenthesis space plus space 4 straight H subscript 2 straight O left parenthesis straight g right parenthesis space space space rightwards harpoon over leftwards harpoon space space space Fe subscript 3 straight O subscript 4 left parenthesis straight s right parenthesis space plus space 4 straight H subscript 2 left parenthesis straight g right parenthesis

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Long Answer Type

103.

Which of the following reactions will get affected by increasing the pressure? Also, mention whether the change will cause the reaction to go into forward or backward direction?

$left parenthesis straight i right parenthesis space COCl subscript 2 left parenthesis straight g right parenthesis space space rightwards harpoon over leftwards harpoon space space space space CO left parenthesis straight g right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis left parenthesis ii right parenthesis space CH subscript 4 left parenthesis straight g right parenthesis space plus space 2 straight S subscript 2 left parenthesis straight g right parenthesis space space space rightwards harpoon over leftwards harpoon space space space space CS subscript 2 left parenthesis straight g right parenthesis plus space 2 straight H subscript 2 straight S left parenthesis straight g right parenthesis left parenthesis iii right parenthesis space CO subscript 2 left parenthesis straight g right parenthesis space plus space straight C left parenthesis straight s right parenthesis space space rightwards harpoon over leftwards harpoon space space 2 CO left parenthesis straight g right parenthesis left parenthesis iv right parenthesis space 2 straight H subscript 2 left parenthesis straight g right parenthesis space plus space CO left parenthesis straight g right parenthesis space space rightwards harpoon over leftwards harpoon space space CH subscript 3 OH left parenthesis straight g right parenthesis left parenthesis straight v right parenthesis space CaCO subscript 3 left parenthesis straight s right parenthesis space rightwards harpoon over leftwards harpoon space space space CaO left parenthesis straight s right parenthesis plus space CO subscript 2 left parenthesis straight g right parenthesis left parenthesis vi right parenthesis space 4 NH subscript 3 left parenthesis straight g right parenthesis space plus space 5 straight O subscript 2 left parenthesis straight g right parenthesis space rightwards harpoon over leftwards harpoon space space 4 NO left parenthesis straight g right parenthesis space plus space 6 straight H subscript 2 straight O left parenthesis straight g right parenthesis$

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Short Answer Type

104. Applying Le-Chatelier’s principle, predict the effect of pressure and temperature on the melting of ice.

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105. Applying Le-Chatelier’s principle, predict the effect of pressure and temperature on the evaporation of water (in a closed vessel).

The equilibrium may be represented as:

The change of water to water vapours is a reversible endothermic (i.e. accompanied by absorption of heat) process. The reaction proceeds with the increase in volume. Hence according to Le-Chatelier’s principle:

(i) With the increase in pressure, the equilibrium tends to shift in that direction in which there occurs a decrease in volume i.e. equilibrium shifts towards left. In other words, the increase in pressure favours the condensation of water vapours into water and decreasing pressure favours vaporisation of water into water vapours i.e. forward reaction is favourable.

(ii) With the increase in temperature, the equilibrium shifts to the right i.e. towards the direction in which heat is absorbed. Thus, increase in temperature favours the vaporisation of water into water vapours.

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Long Answer Type

106. Applying Le-Chatelier’s principle predict the effect of temperature on the solubility of solid substances.

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107. Applying Le-Chatelier’s principle, predict the effect of temperature and pressure on the solubility of gas.

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108. Dihydrogen gas is obtained from natural gas by partial oxidation with steam as per following endothermic reaction:

CH subscript 4 left parenthesis straight g right parenthesis space plus space straight H subscript 2 straight O left parenthesis straight g right parenthesis space space leftwards harpoon over rightwards harpoon space CO left parenthesis straight g right parenthesis space plus space 3 straight H subscript 2 left parenthesis straight g right parenthesis

(a) Write an expression for K_p for the above reaction.
(b) How will the values of K_p and composition of equilibrium mixture be affected by:
(i) increasing the pressure
(ii) increasing the temperature
(iii) using a catalyst?

265 Views

Short Answer Type

109.

Describe the effect of:
(a) addition of H₂(b) addition of CH₃OH
(c) removal of CO
(d) removal of CH₃OH
on the equilibrium of the reaction:

$2 straight H subscript 2 left parenthesis straight g right parenthesis space plus space CO left parenthesis straight g right parenthesis space space rightwards harpoon over leftwards harpoon space space space CH subscript 3 OH left parenthesis straight g right parenthesis$

195 Views

Long Answer Type

110. At 473K, equilibrium constant K_cfor decomposition of phosphorus pentachloride, PCl₅ is 8·3 × 10^–3. If decomposition is depicted as

PCl subscript 5 left parenthesis straight g right parenthesis space space rightwards harpoon over leftwards harpoon space space PCl subscript 3 left parenthesis straight g right parenthesis space plus space Cl subscript 2 left parenthesis straight g right parenthesis comma space space increment subscript straight r straight H to the power of 0 space equals space 124.0 space kJ space mol to the power of negative 1 end exponent

(a) write an expression for K_c for the reaction.

(b) what is the value of K_c for the reverse reaction at the same temperature?

(c) what would be the effect on K_c if:
(i) more PCl₅ is added
(ii) pressure is increased
(iii) temperature is increased?

733 Views