Law of Mass Action

Q.

$NX$ is produced by the following step of reactions:

1. $M+$ $X_2$$⟶$$M{X}_2$

2. $M{X}_2$+$X_2$$⟶$$M_3{X}_8$

3. $M_3{X}_8$+$N_{2}C{O}_3$$⟶$$NX+$$C{O}_2$+$M_3{O}_4$

How much M (metal) is consumed to produce $206g$ of $NX$. (Take atomic weight of $M=56,N=23,X=80$)

1. $42g$

2. $336g$

3. $\frac{7}{4}g$

4. $\frac{14}{3}g$

Q.

For the equilibrium, $\underset{\mathrm{Nitrosyl}\mathrm{chloride}}{2\mathrm{NOCl}\left(\mathrm{g}\right)}\rightleftharpoons \underset{\mathrm{Nitric}\mathrm{oxide}}{2\mathrm{NO}\left(\mathrm{g}\right)}+\underset{\mathrm{chlorine}}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)}$. The value of the equilibrium constant $\mathrm{Kc}$ is $3.75\times {10}^{-4}$ at $1069\mathrm{K}$. Calculate $\mathrm{Kp}$ for the reaction at this temperature.

Q. When the rate of reaction is equal to the rate constant then the order of the reaction is:

1. Zero order
2. First order
3. Second order
4. Third order

Q.

For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.

Q. For which of the following reactions, $K_P=K_C$ ?

1. $N_2\left(g\right)+3H_2\left(g\right)\leftrightharpoons 2N{H}_3\left(g\right)$
2. $PC{l}_3\left(g\right)+C{l}_2\left(g\right)\leftrightharpoons PC{l}_5\left(g\right)$
3. $H_2\left(g\right)+C{l}_2\left(g\right)\leftrightharpoons 2HCl\left(g\right)$
4. $CaC{O}_3\left(s\right)+\leftrightharpoons CaO\left(s\right)+C{O}_2\left(g\right)$

Q.

$\mathrm{pKa}$ of Acetic acid is $4.74$. The concentration of ${\mathrm{CH}}_3\mathrm{COONa}$ is $0.01\mathrm{M}$. The $\mathrm{pH}$ of ${\mathrm{CH}}_3\mathrm{COONa}$ solution is?

Q.

Mention the factors that affect the rate of a chemical reaction.

Q.

How Does Concentration Affect Equilibrium?

Q.

$\underset{\mathrm{Nitrogen}\mathrm{gas}}{{\mathrm{N}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Hydrogen}\mathrm{gas}}{3{\mathrm{H}}_2\left(\mathrm{g}\right)}\rightleftharpoons \underset{\mathrm{Ammonia}}{2{\mathrm{NH}}_3\left(\mathrm{g}\right)}$ for the reaction initially the mole ratio was $1:3$ of ${\mathrm{N}}_2:{\mathrm{H}}_2$. At equilibrium $50\%$ of each has reacted. If the equilibrium pressure is $\mathrm{P}$, the partial pressure of Ammonia at equilibrium is ?

Q.

Write the balanced chemical equation for the reaction of Lead Sulphate from Lead nitrate solution and Dilute sulphuric acid.

Q. 1. In exothermic reaction the activation energy of reactant is 1.less than that of activation energy of product . 2.greater than that of product. 3. Equal 4.none of these

Q. The rate at which a substance reacts depends upon its _____________.

1. active mass
2. molecular mass
3. atomic mass
4. equivalent mass

Q. Theory of active mass indicates that the rate of chemical reaction is directly proportional to the

1. Equilibrium constant
2. Properties of reactants
3. Volume of apparatus
4. Concentration of reactants

Q. The unit of rate constant for the reaction $2{\text{H}}_2+2\text{NO}\to 2{\text{H}}_{2}O+N_2$ which has
Rate $=K\left[H_2\right][NO{]}^2,$ is:

1. ${\text{mol L}}^{-1}{\text{s}}^{-1}$
2. ${\text{s}}^{-1}$
3. ${\text{mol}}^{-2}{\text{L}}^2{\text{s}}^{-1}$
4. ${\text{mol}}^{-1}{\text{L}}^1{\text{s}}^{-1}$

Q.

${\mathrm{N}}_2+{\mathrm{O}}_2\rightleftharpoons 2\mathrm{NO}+\mathrm{Heat}$.

In the above given chemical reaction, which of the following conditions is suitable to get a good yield of $\mathrm{NO}$?

1. Increase in pressure

2. Decrease in pressure

3. Increase in temperature

4. Decrease in temperature

Q. For a reaction between $A$ and $B$ the order with respect to $A$ is $2$ and the order with respect to $B$ is $3$. The concentrations of both $A$ and $B$ are doubled, the rate will increase by a factor of:

1. $12$
2. $16$
3. $32$
4. $10$

Q. Identify the equilibrium reaction in which $K_C$ has no units.

1. Decomposition of $N{H}_3$
2. Decomposition of $HI$
3. All of the above
4. Decomposition of $PC{l}_5$

Q. In a reaction the rate of reaction is proportional to its active mass , this statement is known as

1. Law of mass action
2. Le - chatelier principle
3. Law of constant proportion
   
4. Faraday law of electrolysis

Q.

For the following Assertion and Reason, the correct option is

Assertion (A): When Cu (II) and Sulphide ions are mixed, they react together extremely quickly to give a solid.

Reason (R): The equilibrium constant of Cu²⁺ (aq) + S^2– (aq) ⇌ CuS (s) is high because the solubility product is low.

1. a) (A) is false and (R) is true.

2. b) Both (A) and (R) is false

3. c) Both (A) and (R) are true but (R) is not the explanation for (A).

4. d) Both (A) and (R) are true but (R) is the explanation for (A).

Q. 10 ml of a compound containing N and O is mixed with 30 ml of H2 to produce H2O and 10 ml N2. Molecular formula of compound if both reactants reacts completely
N20
NO2
N2O3
N2O5

Q. For $PC{l}_5\left(g\right)\rightleftharpoons PC{l}_3\left(g\right)+C{l}_2\left(g\right),$ write the expression of $K_c.$

1. $K_c=\frac{\left[PC{l}_3\right]\left[C{l}_2\right]}{\left[PC{l}_5\right]}$
2. $K_c=\frac{\left[PC{l}_5\right]}{\left[PC{l}_3\right]\left[C{l}_2\right]}$
3. $K_c=\frac{\left[PC{l}_3\right]\left[C{l}_2\right]}{[PC{l}_5{]}^5}$
4. $K_c=\frac{\left[PC{l}_3{]}^3\right[C{l}_2{]}^2}{[PC{l}_5{]}^5}$

Q. For the given reaction,
$2A+3B+C\to \text{products}$
Order of reaction with respect to A, B and C are 3, 1 and 0 respectively. What will be the rate law of the given reaction?

1. $R=K\left[A{]}^2\right[B{]}^3\left[C\right]$
2. $R=K\left[A{]}^2\right[B{]}^3$
3. $R=K\left[A{]}^3\right[B{]}^1[C{]}^0$
4. $R=\left[A\right]\left[B{]}^2\right[C{]}^3$

Q. The law of mass action states that at a constant temperature, the rate of a chemical reaction is proportional to the _____ of the reacting substances.

1. total mass
2. molecular weights
3. None of these
4. active masses

Q. Ammonium hydrogen sulphide dissociates according to the equation $N{H}_{4}HS\left(s\right)\rightleftharpoons N{H}_3\left(g\right)+H_{2}S\left(g\right).$ If the observed pressure of the mixture is $1.12atm$ at ${106}^{o}C,$ what is the equilibrium constant $K_p$ of the reaction?

1. $0.314at{m}^2$
2. $1.000at{m}^2$
3. $0.480at{m}^2$
4. $2.000at{m}^2$

Q.

For the reaction A+2B $\rightleftharpoons$ C, the expression for equilibrium constant is

1. [C]/([A][B]²)

2. ([A][B]²)/[C]

3. ([A][B])/[C]

4. [C]/(2[B][A])

Q. The initial pressure of $COC{l}_2$ is $1000$ torr. The total pressure of the system becomes $1500$ torr, when the equilibrium $COC{l}_2\left(g\right)\rightleftharpoons CO\left(g\right)+C{l}_2\left(g\right)$ is attained at constant temperature. The value of $k_p$ (in torr) of the reaction is

1. $1500$
2. $1000$
3. $2500$
4. $500$

Q.

Initial concentration of the reactant is 1 M .. the concentration becomes 0.9 0.8 0.7 in 2 hr , 4 hr, 6 hr respectively then order of the reaction

Ans is 0 pls put it on the paper

Q. Consider the following reactions:
Reaction 1:
$W\to P_1$
Reaction 2:
$X\to P_2$
Reaction 3:
$Y\to P_3$
Reaction 4:
$Z\to P_4$
The order of the above reactions are $0,1,2\&3$ respectively. The graph between $\log \left[rate\right]$ (y-axis) vs. $\log \left[\text{concentration of reactant}\right]$ (x-axis) is plotted.
Which of the following reaction will have the highest slope?

1. Reaction 1
2. Reaction 2
3. Reaction 3
4. Reaction 4

Q. To prepare a buffer solution of $pH=4.04$, amount of Barium acetate to be added to $100\text{mL}$ of $0.1M$ acetic acid solution $\left[p{K}_b\right(C{H}_{3}CO{O}^{-})=9.26]$ is:
Given ${10}^{-0.7}\approx 0.2$

1. 0.05 mole
2. 0.025 mole
3. 0.1 mole
4. 0.005 mole

Q. The vapour density of a gaseous mixture containing only $Ar$ and $N_2{O}_4$ gases is $40$. When the mixture is left for some time, the vapour density is decreased and finally becomes
$\left(37.5\right)$. It happened due to the dissociation of some $N_2{O}_4$ into $N{O}_2$. $(Ar=40)$. What is the degree of dissociation of $N_2{O}_4?$

1. $0.870$
2. $0.780$
3. $0.087$
4. Data is insufficient for calculation