Le Chatelier's Principle

Q. A 20 litre container at 400 K contains $C{O}_{2\left(g\right)}$ at pressure 0.4 atm and an excess of SrO (neglect the volume of solid SrO). The volume of the container is now decreased by moving the movable piston fitted in the container. The maximum volume of the container, when pressure of $C{O}_2$ attains its maximum value, will be
(Given that : $SrC{O}_{3\left(s\right)}\rightleftharpoons Sr{O}_{\left(s\right)}+C{O}_{2\left(g\right)},K_p=1.6atm$ )

1. 10 litre
2. 4 litre
3. 2 litre
4. 5 litre

Q.

How do you solve thermal equilibrium problems?

Q. $K_p$ for the reaction $A\rightleftharpoons B$ is 4. If initially only A is present then what will be the partial pressure of B after equilibrium?

1. 1.2
2. 0.8
3. 0.6
4. 1

Q. Which of the followings is/are incorrect about catalyst?

1. Catalyst alter the position of equilibrium.
   
2. Catalyst increase the rate of both spontaneous and non- spontaneous reaction
3. Catalyst does not initiate any reaction.
4. A small amount of catalyst is required to catalyse a reaction.
   

Q. Of the following which change will shift the reaction towards the product $I_2\left(g\right)\rightleftharpoons 2I\left(g\right),△H_r^0\left(298K\right)=+150kJ$

1. Increase in concentration of $I$
2. Decrease in concentration of $I_2$
3. Increase in temperature
4. Increase in total pressure

Q. For the reaction, $2S{O}_2\left(g\right)+O_2\left(g\right)\rightleftharpoons 2S{O}_3;\Delta H=-57.2kJmo{l}^{-1}and{K}_C=1.7\times {10}^{16}$
Which of the following statement is INCORRECT?

1. The equilibrium constant is large suggestive of reaction going to completion and so no catalyst is required
2. The equilibrium will shift in forward direction as the pressure increases
3. The equilibrium constant decreases as the temperature increases
4. The addition of inert gas at constant volume will not affect the equilibrium constant

Q. $A+B\rightleftharpoons 2C+D$
If $2(E_a{)}_f=(E_a{)}_b;(E_a{)}_f$ = Activation energy for forward reaction, $(E_a{)}_b$ = Activation energy backward reaction. Formation of C will be favoured at

1. Low pressure and high temperature
2. High temperature and high pressure
3. High pressure and low temperature
4. Low temperature and low pressure

Q.

When pressure is increased over the system $ice\rightleftharpoons water$, what will happen ?

1. More ice will form
2. There will be no effect over equilibrium
3. Water will decompose in $H_{2}and{O}_2$
4. More water will form

Q. To an equilibrium mixture of $2S{O}_2\left(g\right)+O_2\left(g\right)\rightleftharpoons 2S{O}_3\left(g\right)$ some helium, an inert gas, is added at constant volume. The addition of helium causes the total pressure to double. Which of the following is true?

1. The concentration of sulphur trioxide increases
2. The number of moles of sulphur trioxide increases
3. The concentration of sulphur dioxide increases
4. The concentration of the three gases is unchanged

Q.

For the reaction $2N{H}_3\left(g\right)\rightleftharpoons N_2\left(g\right)+3H_2\left(g\right),\Delta H=93.6kJmo{l}^{-1}$. Which of the following is incorrect?

1. The pressure changes at constant temperature do not affect the equilibrium constant

2. The volume changes at constant temperature do not affect the equilibrium constant

3. The dissociation of is more favored at high temperature

4. The dissociation of is less favored at high temperature

Q.

The reaction $A+B\rightleftharpoons C+D+heat$ has reached equilibrium. The reaction will move in the forward direction by:

1. Adding more $C$
2. Removing some $A$
3. Decreasing the temperature
4. Removing heat from the system

Q. The equilibrium, $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_2\left(g\right)$ is attained at ${25}^{\circ }C$ in a closed rigid container and an inert gas, helium, is introduced keeping the volume constant. Which of the following statment(s) is/are correct?

1. $\text{Concentrations of}S{O}_2,C{l}_2\text{are changed}$
2. $\text{No effect on equilibrium}$
3. $\text{Concentration of}S{O}_2\text{is reduced}$
4. $K_p\text{of reaction is increasing}$

Q. Which of the following statement(s) is/are $NOT$ correct regarding chemical catalysts?

1. They are not consumed during the chemical reaction.
2. They do not have to be the same phase as the reactant molecules.
3. They cannot make non-spontaneous reactions occur.
4. They shift equilibrated reactions to the product's side.

Q.

Stable complex based on EAN rule:

i) $K_4\left[Fe\right(CN{)}_6]$

ii) $\left[Co\right(N{H}_3{)}_{5}Cl]C{l}_2$

iii) $\left[Ni\right(CO{)}_4]$

iv) $K_2\left[Ni\right(CN{)}_4]$

1. i only
2. i, ii & iii only
3. i & ii only
4. all

Q. The equilibrium $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_2\left(g\right)$ is attained at ${25}^{\circ }$C in a closed rigid container and an inert gas, helium is introduced. Which of the following statement(s) is/are correct?

1. Concentrations of $S{O}_2,C{l}_2$ and $S{O}_{2}C{l}_2$ do not change.
2. More chlorine is formed.
3. Concentration of $S{O}_2$ is reduced.
4. More $S{O}_{2}C{l}_2$ is formed.

Q. The equilibrium $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_g\left(g\right)$ is attained at ${25}^{o}C$ in a closed container and an inert gas, helium is introduced. Which of the following statements are correct?

1. Concentration of $S{O}_2,C{l}_2$ and $S{O}_{2}C{l}_2$ change
2. More chlorine is formed
3. Concentration of $S{O}_2$ is reduced
4. None of the above

Q. Assertion :For the reaction $H_2+I_2\rightleftharpoons 2HI,K_p=K_c$. Reason: If $K_p=K_C$ for a reaction, the sum of stoichiometric coefficient of reactants should be equal to the sum of stoichiometric coefficients of products.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q. For hypothetical reversible reaction, $1/2A_2\left(g\right)+3/2B_2\left(g\right)⟶A{B}_3\left(g\right);\Delta H=-20KJ$ if standard entropies of $A_2,B_2$ and ${AB}_3$ are $60,40$ and $50J{K}^{-1}{mole}^{-1}$ respectively. The above reaction will be in equilibrium at the temperature:

1. $400K$
2. $500K$
3. $250K$
4. $200K$

Q. Partial pressure of $H_2$ in $H_{2}O$ at ${25}^{o}C$ is $1$ bar $k^x$ for $H_2$ in $H_{2}O$ at ${25}^{o}C$ is $71\cdot 18$ bar solubility of $H_2$ in $H_{2}O$ will be:

Q.

The equilibrium, $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_2\left(g\right)$ is attained at ${25}^{\circ }C$ in a closed container and an inert gas, helium, is introduced. Which of the following statements are correct?

1. Concentration of is reduced

2. More chlorine is formed

3. Concentrations of and are not changed

4. More is formed

Q. Which of the following stresses to a system at equilibrium cause an increase in the production of $C{H}_{3}OH?CO\left(g\right)+2H_2\left(g\right)\to C{H}_{3}OH\left(l\right)$
$\left(a\right)H_2$ is added
(b) The volume is increase
(c) Argon is added (at constant volume)
(d) Removing CO

1. (a) only
2. (b), (c), (d)
3. (c), (d)
4. (b) only

Q. Free energy change for a reversible process is:

1. $>0$
2. $<0$
3. equal to zero
4. unpredictable

Q.

The equilibrium, $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_2\left(g\right)$ is attained at ${25}^{\circ }C$ in a closed container and an inert gas, helium, is introduced. Which of the following statements are correct?

1. Concentrations of $S{O}_2,C{l}_2$ and $S{O}_{2}C{l}_2$ are not changed

2. More chlorine is formed

3. Concentration of $S{O}_2$ is reduced

4. More $S{O}_{2}C{l}_2$ is formed

Q. The equilibrium $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_g\left(g\right)$ is attained at ${25}^{o}C$ in a closed container and an inert gas, helium is introduced. Which of the following statements are correct?

1. Concentration of $S{O}_2,C{l}_2$ and $S{O}_{2}C{l}_2$ change
2. More chlorine is formed
3. Concentration of $S{O}_2$ is reduced
4. None of the above

Q. Assertion :Adding inert gas to dissociation equilibrium of $N_2{O}_4$ at constant pressure and temperature increases the dissociation. Reason: Molar concentration of the reactants and products decreases.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Assertion is incorrect but Reason is correct

Q.

When pressure is increased over the system $ice\rightleftharpoons water$, what will happen ?

1. More water will form
2. More ice will form
3. There will be no effect over equilibrium
4. Water will decompose in H₂ and O₂

Q. Of the following which change will shift the reaction towards the product $I_2\left(g\right)\rightleftharpoons 2I\left(g\right),△H_r^0\left(298K\right)=+150kJ$

1. Increase in concentration of $I$
2. Decrease in concentration of $I_2$
3. Increase in temperature
4. Increase in total pressure

Q. Which one of the following conditions will favour maximum formation of the product in the reaction,
$A_2\left(g\right)+B_2\left(g\right)\rightleftharpoons X_2\left(g\right);{\Delta }_{r}H=-XkJ$ ?

1. High temperature and low pressure
2. Low temperature and high pressure
3. High temperature and high pressure
4. Low temperature and low pressure

Q.

The equilibrium, $S{O}_{2}C{l}_2\left(g\right)\rightleftharpoons S{O}_2\left(g\right)+C{l}_2\left(g\right)$ is attained at ${25}^{\circ }C$ in a closed container and an inert gas, helium, is introduced. Which of the following statements are correct?

1. Concentrations of $S{O}_2,C{l}_2$ and $S{O}_{2}C{l}_2$ are not changed

2. More chlorine is formed

3. Concentration of $S{O}_2$ is reduced

4. More $S{O}_{2}C{l}_2$ is formed

Q. The degree of dissociation of $PC{I}_5\left(g\right)\rightleftharpoons PC{I}_3\left(g\right)+C{I}_2\left(g\right)$ , decreases with increase in ______ at equilibrium?

1. volume
2. concentration
3. pressure
4. temperature