In which of the following case, does the reaction go farthest to completion?

• K= 10²

• K = 10

• K = 10^-2

• K = 1

pH of a buffer solution decreases by 0.02 units when 0.12 g of acetic acid is added to 250 mL of a buffer solution of acetic acid and potassium acetate at 27C. The buffer capacity of the solution is

• 0.1

• 10

• 1

• 0.4

The equilibrium constant for the given reaction is 100.

${\mathrm{N}}_2\left(\mathrm{g}\right) + 2{\mathrm{O}}_2\left(\mathrm{g}\right) \rightleftharpoons 2{\mathrm{NO}}_2\left(\mathrm{g}\right)$

What is the equilibrium constant for the reaction given below? 

${\mathrm{NO}}_2\left(\mathrm{g}\right) \rightleftharpoons \frac{1}{2} {\mathrm{N}}_2\left(\mathrm{g}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right)$

• 10

• 1

• 0.1

• 0.01

20 mL of 0.1 M acetic acid is mixed with 50 mL of potassium acetate. K_a of acetic acid = 1.8 x 10^-5 at 27C. Calculate concentration of potassium acetate if pH of the mixture is 4.8.

• 0.1 M

• 0.04 M

• 0.4 M

• 0.02 M

415.

The standard free energy change of a reaction is $∆\mathrm{G}°= -115 \mathrm{kJ} \mathrm{at} 298 \mathrm{K}.$ Calculate the equilibrium constant K_p in log K_p (R =8.314 JK ^-1mol^-1 ).

• 20.16

• 2.303

• 2.016

• 13.83

Given the equilibrium system:

${\mathrm{NH}}_4\mathrm{Cl}\left(\mathrm{s}\right) \to {\mathrm{NH}}_4^{+}\left(\mathrm{aq}\right) + {\mathrm{Cl}}^{-}\left(\mathrm{aq}\right) (∆\mathrm{H} =+3.5 \mathrm{kcal}/\mathrm{mol}).$

What change will shift the equilibrium to the right?

• Decreasing the temperature

• Increasing the temperature

• Dissolving NaCl crystals in the equilibrium mixture

• Dissolving NH₄NO₃ crystals in the equilibrium mixture

Equivalent amounts of H₂ and I₂, are heated in a closed vessel till equilibrium is obtained. If 80% of the hydrogen can be converted to HI, the K_c at this temperature is :

• 64

• 16

• 0.25

• 4

For the reaction ${\mathrm{H}}_2\left(\mathrm{g}\right) + {\mathrm{I}}_2\left(\mathrm{g}\right) \to 2\mathrm{HI}\left(\mathrm{g}\right),$ the equilibrium constant K_P changes with: 

• total pressure

• catalyst

• the amount H₂ and I₂

• temperature

In a closed container, a liquid is stirred with a paddle to increase the temperature. Which of the following is true ?

• $∆\mathrm{E} = \mathrm{W} \ne 0, \mathrm{q}= 0$

• $∆\mathrm{E} = \mathrm{W} =\mathrm{q} \ne 0$

• $∆\mathrm{E} =0, \mathrm{W} = \mathrm{q}\ne 0$

• $\mathrm{W} =0, ∆\mathrm{E}= \mathrm{q}\ne 0$

If an allotropic form changes slowly to a stable form. It is called

• enantiotropy

• dynamic allotropy

• monotropy

• None of the above