Le Chatelier's Principle for Del N Equals to 0

Q.

Why does addition of inert gas at constant volume not affect equilibrium of system but addition of inert gas at constant pressure does affect it?

Q. Which of the following substance gives a positively charged sol?

1. Gold
2. Arsenious sulphide
3. Starch
4. Ferric hydroxide

Q.

Why concentrations of pure solids and liquids taken to be Unity in case of equilibrium constant?

Q.

What do you mean by the rate-determining step?

Q. Solubility of a gas in water depends on

1. Nature of gas
2. Temperature
3. Pressure of the gas
4. All the above

Q. 41. When a gas is bubbled through water at 298K a very dilute solution is obtained. Henry constant is 100 Kbar. If gas exerts partial pressure 1 bar the number of millimoles in 1L water is?

Q. The rate constant of a reaction increases by five times on increase in temperature from ${27}^{o}C$ to ${52}^{o}C$. The value of activation energy in ${\text{kJ mol}}^{-1}$ is:
(Rounded off to the nearest integer)
$[R=8.314J{K}^{-1}mo{l}^{-1}]$

Q.

Mechanism of a hypothetical reaction ${\mathrm{X}}_2+{\mathrm{Y}}_2\to 2\mathrm{XY}$ is given below.$\left(\mathrm{i}\right){\mathrm{X}}_2\rightleftharpoons \mathrm{X}+\mathrm{X}\left(\mathrm{fast}\right)\left(\mathrm{ii}\right)\mathrm{X}+{\mathrm{Y}}_2\to \mathrm{XY}+\mathrm{Y}\left(\mathrm{slow}\right)\left(\mathrm{iii}\right)\mathrm{X}+\mathrm{Y}\to \mathrm{XY}\left(\mathrm{fast}\right)$What will be the overall order of the reaction?

Q. The equilibrium reaction that is not influenced by volume change at constant temperature is:

1. $2NO\left(g\right)+O_2\left(g\right)\rightleftharpoons 2N{O}_2\left(g\right)$
2. $H_2\left(g\right)+I_2\left(g\right)\rightleftharpoons 2HI\left(g\right)$
3. $N_2\left(g\right)+3H_2\left(g\right)\rightleftharpoons 2N{H}_3\left(g\right)$
4. $N_2{O}_4\left(g\right)\rightleftharpoons 2N{O}_2\left(g\right)$

Q.

Densities of diamond and graphite are 3.5 and 2.3 g/ml respectively. Increase of pressure on the equilibrium:

1. Has no effect

2. Favours forward reaction

3. Favors backward reaction

4. Increases the reaction rate

Q.

Which of the following reactions will get affected by increasing the pressure?
Also, mention whether change will cause the reaction to go into forward or backward direction.
(i) $COC{l}_2\left(g\right)\leftrightarrow CO\left(g\right)+C{l}_2\left(g\right)$
(ii) $C{H}_4\left(g\right)+2S_2\left(g\right)\leftrightarrow C{S}_2\left(g\right)+2H_{2}S\left(g\right)$
(iii) $C{O}_2\left(g\right)+C\left(s\right)\leftrightarrow 2CO\left(g\right)$
(iv) $2H_2\left(g\right)+CO\left(g\right)\leftrightarrow C{H}_{3}OH\left(g\right)$
(v) $CaC{O}_3\left(s\right)\leftrightarrow CaO\left(s\right)+C{O}_2\left(g\right)$
(vi) $4N{H}_3\left(g\right)+5O_2\left(g\right)\leftrightarrow 4NO\left(g\right)+6H_{2}O\left(g\right)$

Q.

Arun has prepared $0.01\%$ (by mass) solution of sodium chloride in water. Which of the following correctly represents the composition of the solutions?

1. $1.00\mathrm{g}\mathrm{of}\mathrm{NaCl}+100\mathrm{g}\mathrm{of}\mathrm{water}$

2. $0.11\mathrm{g}\mathrm{of}\mathrm{NaCl}+100\mathrm{g}\mathrm{of}\mathrm{water}$

3. $0.01\mathrm{g}\mathrm{of}\mathrm{NaCl}+99.99\mathrm{g}\mathrm{of}\mathrm{water}$

4. $0.10\mathrm{g}\mathrm{of}\mathrm{NaCl}+99.90\mathrm{g}\mathrm{of}\mathrm{water}$

Q. Can liquid convert into solid by applying pressure?

Q. For the gas phase reaction,
$C_2{H}_4\left(g\right)+H_2\left(g\right)\rightleftharpoons C_2{H}_6\left(g\right);△H^o=-136.8kJmo{l}^{-1}$
carried out in a vessel, the equilibrium concentration of $C_2{H}_4$ can be increased by:

1. Increasing the temperature
2. Decreasing the pressure
3. Removing some $H_2$
4. Adding some $C_2{H}_6$

Q.

Which enthalpy is always positive?

Q. For the gaseous reaction, $pA+qB\rightleftharpoons qC+pD$, which of the following relationship is true?

1. 
2. 
3. 
4. 

Q.

For gaseous reactions, if $\Delta H$ is the change in enthalpy & $\Delta U$ that in internal energy, then

1. only if the number of mole of product is less than that of reactants

2. only if the number of mole of the reactants is less than that of the products.

3. is always less than

4. is always greater than

Q.

What is reversible reaction example?

Q.

On increasing the temperature of the reacting system by 10^o the rate of reaction becomes almost double. The most appropriate reason for this is

1. The fraction of molecules having threshold energy increases

2. The value of threshold energy decreases

3. Activation energy decreases by increase of temperature

4. Collision frequency increases

Q.

Find the odd one out and give reason for the choice.

1. Wood

2. Paper

3. Plastic

4. Silver

Q. The ability of anion, to bring about coagulation of a given colloid, depends upon

1. Magnitude of the charge
2. Both magnitude and charge
3. Its charge only
4. Sign of the charge alone

Q.

Identify the physical state of the solute in blue vitriol $(CuS{O}_4.5H_{2}O).$

Q. For the reversible reaction:

1. by increasing the concentration of $N{H}_3\left(g\right)$
2. by decreasing the pressure
3. by decreasing the concentrations of $N_2\left(g\right)$ and $H_2\left(g\right)$
4. by increasing pressure and decreasing temperature

Q.

On what factors do the equilibrium position and equilibrium constant depend? Explain by giving appropriate reasons.

Q.

In the reaction ${\mathrm{N}}_2+{\mathrm{O}}_2\to 2\mathrm{NO}-\mathrm{Heat}$ which of the following conditions is suitable to get a good yield of $\mathrm{NO}$?

1. Increase in temperature

2. Decrease in temperature

3. Increase in pressure

4. The addition of a catalyst

Q. NH4COONH2 (s) 2NH3 (g) + CO2 (g). If equilibrium pressure of gaseous mixture is 3 atm then Kp will be 1) 4 2) 27 3) 4/27 4)1/27

Q. According to le-Chatelier 's principle, adding heat to a solid and liquid in equilibrium will cause the :

1. Amount of solid to decrease
2. Amount of liquid to decrease
3. Temperature to rise
4. Temperature to fall

Q.

How do you know if equilibrium favours your product?

Q. For the reaction, $2S{O}_2\left(g\right)+O_2\left(g\right)\rightleftharpoons 2S{O}_3\left(g\right),△H=-57.2kJmo{l}^{-1}$ 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 constant decreases as the temperature increases
3. The equilibrium will shift in forward direction as the pressure increase
4. The addition of inert gas at constant volume will not affect the equilibrium constant

Q.

All energetically effective collisions do not result in a chemical change. Explain with the help of an example.