### Chemistry - Chemical Equilibirium

#### Question - 1

Which one of the following is a reversible process ?

• A mixing of gases by diffusion
• B dissociation of a  solute in pure solvent
• C expansion of a gas in vacuum
• D melting of ice without rise in temprature.

#### Question - 2

Which one of the following equilibriums moves backward when pressure is applied ?

• A $N_{2}(g) + 3H_{2}(g) \rightleftharpoons 2NH_{3}(g)$
• B $N_{2}(g) + O_{2}(g) \rightleftharpoons 2NO(g)$
• C $Water??\rightleftharpoons Ice$
• D $I_{2}(g)\rightleftharpoons I_{2}(S)$

#### Question - 3

For reversible reaction in equilibrium, in which one of the following cases less products would be formed ?

• A temperature is raised ($\triangle$H is positive)
• B temperature is raised ($\triangle$H is negative)
• C pressure is lowered ($\triangle$H is negative)
• D noble gas is added while the pressure remains unchanged.

#### Question - 4

In the system $CaF_{2}(S)=Ca^{2+}(aq)+2\overline{F}(g),$ increasing the concentration of $Ca^{2+}$(aq) four times will cause the equilibrium concentration of  $\overline F$ change to

• A 1/2 times of the initial value
• B 1/4 times of the initial value
• C 2 times of the initial value
• D 4 times of the initial value

#### Question - 5

$K_{p}$ for the reaction
​​​​​​​$A(g)+2B(g)\rightleftharpoons 2C(g)+D(s)$ is

• A $[C^{2}]\over[A][B^{2}]$
• B $[C^{2}]\over[A][B]^{2}$
• C $[C^{2}][D]\over[A][B]^{2}$
• D $[A][B]^{2}\over[C^{2}][B]$

#### Question - 6

Which one of the following reactions has the least tendency to go to completion?

• A $2H_{2}(g)+O_{2}(g)\rightleftharpoons 2H_{2}O; \ K=1.7\times10^{27}$
• B $N_{2}(g)+O_{2}(g)\rightleftharpoons 2NO;\ K=5.0\times 10^{-31}$
• C $H_{2}(g)+C1_{2}(g)\rightleftharpoons 2HC1(g); \ K=3.2\times10^{16}$
• D $2NOC1(g)\rightleftharpoons 2NO(g)+C1_{2}(g);$

#### Question - 7

What is the unit of $K_{c}$ for the following equilibria $2NO(g)+C1_{2}\rightleftharpoons 2NOC1(g)$

• A $mol\ l^{-1}$
• B $l mol^{-1}$
• C $l\ cm^{-1}$
• D no units

#### Question - 8

For the following two equilibria
$SO_{2}(g)+1/2O_{2}(g)\rightleftharpoons SO_{3}(g); K_{1}$
$2SO_{3}(g)\rightleftharpoons 2SO_{2}(g)+O_{2}(g); K_{2}$

The values of equilibrium constants are related by

• A $K_{2}=K_{1}^{2}$
• B $K_{2}+{1\over K^{2}_{1}}$
• C $K_{2}=K_{1}$
• D $K_{2}={1\over K_{1}}$

#### Question - 9

In which of the following does the reaction go almost to completion?

• A $K_{c}=10^{3}$
• B $K_{c}=10^{2}$
• C $K_{c}=10^{-2}$
• D $K_{c}=10^{-3}$

#### Question - 10

Conisider the reaction $A(g)+B(g)??\rightleftharpoons C(g)+D(g)$  Which occurs in one step. The specific rate constants are 0.25 and $5.0\times 10^{13}$ for the forward and reverse reactions respectively.  The value of equilibrium constant would be

• A $2.25\times10^{-6}$
• B $5.0\times10^{-5}$
• C $4.0\times10^{2}$
• D $2.0\times10^{4}$