Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 12: Problem 9

Given the following descriptions of reversible reactions, write a balanced equation (simplest whole-number coefficients) and the equilibrium constant expression \((K)\) for each. (a) Nitrogen gas reacts with solid sodium carbonate and solid carbon to produce carbon monoxide gas and solid sodium cyanide. (b) Solid magnesium nitride reacts with water vapor to form magnesium hydroxide solid and ammonia gas. (c) Ammonium ion in aqueous solution reacts with a strong base at \(25^{\circ} \mathrm{C}\), giving aqueous ammonia and water. (c) Hydrogen sulfide gas \(\left(\mathrm{H}_{2} \mathrm{~S}\right)\) bubbled into an aqueous solution of lead(II) ions produces lead sulfide precipitate and hydrogen ions.

Short Answer

Expert verified
#Answer# a) \(K = \frac{[\mathrm{CO}]^3}{[\mathrm{N}_2]}\) b) \(K = \frac{[\mathrm{NH}_3]^2}{[\mathrm{H}_2\mathrm{O}]^6}\) c) \(K = \frac{[\mathrm{NH}_3]}{[\mathrm{NH}_4^+][\mathrm{OH}^-]}\) d) \(K = \frac{[\mathrm{H}^+]^2}{[\mathrm{H}_2\mathrm{S}][\mathrm{Pb}^{2+}]}\)

Step by step solution

01

a) Nitrogen gas reacts with solid sodium carbonate and solid carbon

Write the balanced chemical equation for this reaction: $$ \mathrm{N}_2(g) + 2\mathrm{Na}_2\mathrm{CO}_3(s) + 3\mathrm{C}(s) \rightleftharpoons 2\mathrm{NaCN}(s) + 3\mathrm{CO}(g) $$ Now, write the equilibrium constant expression: $$ K = \frac{[\mathrm{CO}]^3}{[\mathrm{N}_2]} $$ Keep in mind that the concentrations of pure solids (like \(\mathrm{Na}_2\mathrm{CO}_3\), \(\mathrm{C}\), and \(\mathrm{NaCN}\)) are not included in the equilibrium expression.
02

b) Solid magnesium nitride reacts with water vapor

Write the balanced chemical equation for this reaction: $$ \mathrm{Mg}_3\mathrm{N}_2(s) + 6\mathrm{H}_2\mathrm{O}(g) \rightleftharpoons 3\mathrm{Mg(OH)}_2(s) + 2\mathrm{NH}_3(g) $$ Now, write the equilibrium constant expression: $$ K = \frac{[\mathrm{NH}_3]^2}{[\mathrm{H}_2\mathrm{O}]^6} $$ Again, the concentrations of pure solids (like \(\mathrm{Mg}_3\mathrm{N}_2\) and \(\mathrm{Mg(OH)}_2\)) are not included in the equilibrium expression.
03

c) Ammonium ion in aqueous solution reacts with a strong base

Write the balanced chemical equation for this reaction: $$ \mathrm{NH}_4^+(aq) + \mathrm{OH}^-(aq) \rightleftharpoons \mathrm{NH}_3(aq) + \mathrm{H}_2\mathrm{O}(l) $$ Now, write the equilibrium constant expression: $$ K = \frac{[\mathrm{NH}_3]}{[\mathrm{NH}_4^+][\mathrm{OH}^-]} $$ In this case, water is not included in the equilibrium expression because it is a pure liquid.
04

d) Hydrogen sulfide gas reacts with lead(II) ions in an aqueous solution

Write the balanced chemical equation for this reaction: $$ \mathrm{H}_2\mathrm{S}(g) + \mathrm{Pb}^{2+}(aq) \rightleftharpoons \mathrm{PbS}(s) + 2\mathrm{H}^+(aq) $$ Now, write the equilibrium constant expression: $$ K = \frac{[\mathrm{H}^+]^2}{[\mathrm{H}_2\mathrm{S}][\mathrm{Pb}^{2+}]} $$ In this case, the concentration of pure solid lead sulfide (PbS) is not included in the equilibrium expression.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Given the following reactions and their equilibrium constants, $$\begin{array}{cl}\mathrm{C}(s)+\mathrm{CO}_{2}(g) \rightleftharpoons 2 \mathrm{CO}(g) & K=2.4 \times 10^{-9} \\ \mathrm{COCl}_{2}(g) \rightleftharpoons \mathrm{CO}(g)+\mathrm{Cl}_{2}(g) & K=8.8 \times 10^{-13} \end{array}$$ calculate \(K\) for the reaction $$\mathrm{C}(s)+\mathrm{CO}_{2}(g)+2 \mathrm{Cl}_{2}(g) \rightleftharpoons 2 \mathrm{COCl}_{2}(g)$$

Carbonyl fluoride, \(\mathrm{COF}_{2}\), is an important intermediate for organic fluorine compounds. It can be prepared by the following reaction: $$\mathrm{CO}_{2}(\mathrm{~g})+\mathrm{CF}_{4}(g) \rightleftharpoons 2 \mathrm{COF}_{2}(g)$$ At \(1000^{\circ} \mathrm{C}, K\) for this reaction is \(0.50 .\) What are the partial pressures of all the gases at equilibrium when the initial partial pressures of \(\mathrm{CO}_{2}\) and \(\mathrm{CF}_{4}\) are \(0.713 \mathrm{~atm} ?\)

Consider the statement "The equilibrium constant for a reaction at \(400 \mathrm{~K}\) is 792 . It must be a very fast reaction." What is wrong with the statement?

Consider the equilibrium $$\mathrm{C}(s)+\mathrm{CO}_{2}(g) \rightleftharpoons 2 \mathrm{CO}(g)$$ When this system is at equilibrium at \(700^{\circ} \mathrm{C}\) in a \(2.0\) - \(\mathrm{L}\) container, \(0.10 \mathrm{~mol}\) \(\mathrm{CO}, 0.20 \mathrm{~mol} \mathrm{CO}_{2}\), and \(0.40 \mathrm{~mol} \mathrm{C}\) are present. When the system is cooled to \(600^{\circ} \mathrm{C}\), an additional \(0.040 \mathrm{~mol} \mathrm{C}(s)\) forms. Calculate \(K\) at \(700^{\circ} \mathrm{C}\) and again at \(600^{\circ} \mathrm{C}\).

For the following reactions, predict whether the pressure of the reactants or products increases or remains the same when the volume of the reaction vessel is increased. (a) \(\mathrm{H}_{2} \mathrm{O}(l) \rightleftharpoons \mathrm{H}_{2} \mathrm{O}(g)\) (b) \(\mathrm{N}_{2}(g)+3 \mathrm{H}_{2}(g) \rightleftharpoons 2 \mathrm{NH}_{3}(g)\) (c) \(\mathrm{C}_{2} \mathrm{H}_{4}(g)+\mathrm{H}_{2} \mathrm{O}(g) \rightleftharpoons \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{OH}(g)\)
See all solutions

Recommended explanations on Chemistry Textbooks

Chemical Reactions

Read Explanation

Chemical Analysis

Read Explanation

Kinetics

Read Explanation

The Earths Atmosphere

Read Explanation

Inorganic Chemistry

Read Explanation

Nuclear Chemistry

Read Explanation
View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free