Class 11Chemistry6-1.Equilibrium (Chemical Equilibrium)Mix Examples- 6-1.Equilibrium (Chemical Equilibrium)
Medium$6.9 \ g$ of $N_2O_4$ is taken in a $0.5 \ L$ closed vessel at $400 \ K$. For the equilibrium $N_2O_{4(g)} \rightleftharpoons 2NO_{2(g)}$,the total pressure at equilibrium is $9.15 \ atm$. Calculate $K_c$,$K_p$,and the partial pressure of each component.
(A) $1$. Moles of $N_2O_4$ initially: $n = \frac{6.9 \ g}{92 \ g/mol} = 0.075 \ mol$.
$2$. Initial pressure $P_i$ of $N_2O_4$: $P_i = \frac{nRT}{V} = \frac{0.075 \times 0.0821 \times 400}{0.5} = 4.926 \ atm$.
$3$. Let $x$ be the degree of dissociation. At equilibrium: $P_{N_2O_4} = P_i(1-x)$ and $P_{NO_2} = 2P_ix$.
$4$. Total pressure $P_T = P_i(1-x) + 2P_ix = P_i(1+x) = 9.15 \ atm$.
$5$. $1+x = \frac{9.15}{4.926} \approx 1.857$,so $x = 0.857$.
$6$. Partial pressures: $P_{N_2O_4} = 4.926(1-0.857) = 0.704 \ atm$ and $P_{NO_2} = 2 \times 4.926 \times 0.857 = 8.442 \ atm$.
$7$. $K_p = \frac{(P_{NO_2})^2}{P_{N_2O_4}} = \frac{(8.442)^2}{0.704} \approx 101.25 \ atm$.
$8$. $K_c = K_p(RT)^{-\Delta n} = 101.25 \times (0.0821 \times 400)^{-1} = \frac{101.25}{32.84} \approx 3.083 \ mol \ L^{-1}$.
$2$. Initial pressure $P_i$ of $N_2O_4$: $P_i = \frac{nRT}{V} = \frac{0.075 \times 0.0821 \times 400}{0.5} = 4.926 \ atm$.
$3$. Let $x$ be the degree of dissociation. At equilibrium: $P_{N_2O_4} = P_i(1-x)$ and $P_{NO_2} = 2P_ix$.
$4$. Total pressure $P_T = P_i(1-x) + 2P_ix = P_i(1+x) = 9.15 \ atm$.
$5$. $1+x = \frac{9.15}{4.926} \approx 1.857$,so $x = 0.857$.
$6$. Partial pressures: $P_{N_2O_4} = 4.926(1-0.857) = 0.704 \ atm$ and $P_{NO_2} = 2 \times 4.926 \times 0.857 = 8.442 \ atm$.
$7$. $K_p = \frac{(P_{NO_2})^2}{P_{N_2O_4}} = \frac{(8.442)^2}{0.704} \approx 101.25 \ atm$.
$8$. $K_c = K_p(RT)^{-\Delta n} = 101.25 \times (0.0821 \times 400)^{-1} = \frac{101.25}{32.84} \approx 3.083 \ mol \ L^{-1}$.
Explore More
Similar Questions
The equilibrium constants of the following are
$N_2 + 3H_2 \rightleftharpoons 2NH_3 \,; \quad K_1$
$N_2 + O_2 \rightleftharpoons 2NO \,; \quad K_2$
$H_2 + \frac{1}{2} O_2 \rightleftharpoons H_2O \,; \quad K_3$
The equilibrium constant $(K)$ of the reaction:
$2NH_3 + \frac{5}{2} O_2 \rightleftharpoons 2NO + 3H_2O$ is:
$N_2 + 3H_2 \rightleftharpoons 2NH_3 \,; \quad K_1$
$N_2 + O_2 \rightleftharpoons 2NO \,; \quad K_2$
$H_2 + \frac{1}{2} O_2 \rightleftharpoons H_2O \,; \quad K_3$
The equilibrium constant $(K)$ of the reaction:
$2NH_3 + \frac{5}{2} O_2 \rightleftharpoons 2NO + 3H_2O$ is:
DifficultAIPMT 2003
View SolutionWhen $1 \ mol$ of $H_2$ and $1 \ mol$ of $N_2$ are enclosed in a $5 \ L$ vessel and the reaction is allowed to attain equilibrium,it is found that at equilibrium there is $x \ mol$ of $H_2$. The number of moles of $NH_3$ would be
Medium
View SolutionAt $T \ K$,$K_c$ for the reaction $AO_{2(g)} + BO_{2(g)} \rightleftharpoons AO_{3(g)} + BO_{(g)}$ is $16$. One mole each of reactants and products are taken in a $1 \ L$ flask and heated to $T \ K$,and equilibrium is established. What is the equilibrium concentration of $BO$ (in $mol \ L^{-1}$)?
For the reaction $Br_2 \rightleftharpoons 2Br$,the equilibrium constants at $327\,^oC$ and $527\,^oC$ are $6.1 \times 10^{-12}$ and $1.0 \times 10^{-7}$ respectively. The reaction is ...........
Easy
View SolutionCalculate:
$(a)$ $\Delta G^{\circ}$ and
$(b)$ the equilibrium constant for the formation of $NO_2$ from $NO$ and $O_2$ at $298 \, K$
$NO_{(g)} + 1/2 O_{2(g)} \longleftrightarrow NO_{2(g)}$
Given:
$\Delta G^{\circ}_f(NO_2) = 52.0 \, kJ/mol$
$\Delta G^{\circ}_f(NO) = 87.0 \, kJ/mol$
$\Delta G^{\circ}_f(O_2) = 0 \, kJ/mol$
$(a)$ $\Delta G^{\circ}$ and
$(b)$ the equilibrium constant for the formation of $NO_2$ from $NO$ and $O_2$ at $298 \, K$
$NO_{(g)} + 1/2 O_{2(g)} \longleftrightarrow NO_{2(g)}$
Given:
$\Delta G^{\circ}_f(NO_2) = 52.0 \, kJ/mol$
$\Delta G^{\circ}_f(NO) = 87.0 \, kJ/mol$
$\Delta G^{\circ}_f(O_2) = 0 \, kJ/mol$
Medium
View SolutionVedclass Products
For Students
Vedclass Test Series
Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Live online exams with unlimited students, 360° analytics & white-label branding.
See Demo