35. For an equilibrium H2O(s) = H2O(l) which of the following statements is true.
(A) The pressure changes do not affect the equilibrium
(B) More of ice melts if pressure on the system is increased
(C) More of liquid freezes if pressure on the system in increased
(D)The pressure changes may increased of decreases the degree of advancement of the reaction depending
upon the temperature of type system
Answers
Answer:
35)A....................... .....
For an equilibrium H2O(s) = H2O(l) which of the following statements is true.
(B) More of ice melts if pressure on the system is increased
Explanation:
This can be explained on the basis of : Le chatlier's principle
Le chartlier’s principle: We know that at equilibrium, the state variables become constant. If we disturb any state variable, the reaction gets disturbed and the reaction diverts itself in a direction where disturbance is reduced.
So, according to this “ if any kind of reaction is subjected to any kind of stress, then the reaction proceeds in a direction where the stress gets reduced “.
(a) Effect of change in concentration : For this consider a reaction:
N₂ + 3H₂---> 2NH₃
• In this if concentration of nitrogen gas is increased, the reaction will get disturbed. It will proceed in a direction in which the concentration of nitrogen gas is reduced i.e in forward direction.
It is to be noted:
• If concentrations of reactants are increased, then the reaction favors products.
• If concentration of products is increased, then the reaction favors backward reaction.
(b) Effect of temperature: We have two types of reactions: Endothermic and Exothermic.
• If we increase the temperature, the reaction proceeds in such a direction in which the heat is absorbed i.e endothermic side is favoured.
• If we decrease the temperature, the reaction proceeds in such a direction in which the heat is released i.e exothermic side is favoured.
(c) Effect of change of Pressure
• If we increase the pressure, it will take the reaction towards lesser number of moles i.e towards products.
• If we decrease the pressure, it will take the reaction towards more number of moles that is towards reactants
(d)Effect of change in Volume
• According to Boyle’s law, we know pressure is inversely proportional to volume .So, if we increase the volume, moles per litre decreases. Therefore, the reactions move in that reaction in which moles per litre is increased.
• If we decrease the volume, moles per litre increase .Therefore, the reaction move in that reaction in which moles per litre is decreased.
(d) Introduction of Inert gas
• Whenever inert gas is introduced in any reaction, the inertness of reaction occurs but doesn’t affect equilibrium.
• Inert gas introduced at constant volume does not affect equilibrium. Inert gas introduced at constant pressure: leads to increase in volume, moles per litre decreases and the reaction moves in the direction where moles per litre increases.
(e) Effect of catalyst: It just increases the rate of reaction without getting consumed.