Explanations 
Textbooks 
Flashcards 
91影视 AI 
Notes 
Study Plans 
Study Sets 
Find a degree 
Magazine Chapter 18: Problem 47
Write equations for the salt hydrolysis reactions occuring when the following salts dissolve in water. Classify each as acidic, basic, or neutral. \begin{equation} \begin{array}{l}{\text { a. ammonium nitrate } \quad \text { c. rubidium acetate }} \\ {\text { b. potassium sulfate}} \quad\quad {\text {d. calcium carbonate }}\end{array} \end{equation}
Short Answer
Expert verified
a. Acidic; b. Neutral; c. Basic; d. Basic.
Step by step solution
01
Understand Salt Hydrolysis
Salt hydrolysis involves the reaction of a salt with water to form an acidic or basic solution. It's important to determine if the resulting solutions are acidic, basic, or neutral by considering the strengths of the parent acids and bases from which the salts are derived.
02
Determine Hydrolysis and Solution Type for Ammonium Nitrate
Ammonium nitrate (NH鈧凬O鈧�) dissolves in water to form ammonium ions (NH鈧勨伜) and nitrate ions (NO鈧冣伝). The ammonium ion is the conjugate acid of a weak base (NH鈧�), leading to the following hydrolysis reaction: \[ NH_4^+ + H_2O \rightleftharpoons NH_3 + H_3O^+ \] This produces hydronium ions, making the solution acidic.
03
Determine Hydrolysis and Solution Type for Potassium Sulfate
Potassium sulfate (K鈧係O鈧�) dissociates completely into potassium ions (K鈦�) and sulfate ions (SO鈧劼测伝). Potassium ion is derived from a strong base (KOH) and sulfate ion from a strong acid (H鈧係O鈧�), so neither ion hydrolyzes significantly. Thus, the solution remains neutral.
04
Determine Hydrolysis and Solution Type for Rubidium Acetate
Rubidium acetate (RbCH鈧僀OO) dissociates into rubidium ions (Rb鈦�) and acetate ions (CH鈧僀OO鈦�). The acetate ion, being the conjugate base of the weak acid acetic acid (CH鈧僀OOH), reacts with water: \[ CH_3COO^- + H_2O \rightleftharpoons CH_3COOH + OH^- \] This increases hydroxide ions, making the solution basic.
05
Determine Hydrolysis and Solution Type for Calcium Carbonate
Calcium carbonate (CaCO鈧�) dissociates into calcium ions (Ca虏鈦�) and carbonate ions (CO鈧兟测伝). The carbonate ion is the conjugate base of the weak acid carbonic acid (H鈧侰O鈧�), leading to hydrolysis: \[ CO_3^{2-} + H_2O \rightleftharpoons HCO_3^- + OH^- \] As this increases hydroxide ions, the solution is basic.
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.
Over 30 million students worldwide already upgrade their learning with 91影视!
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
Acidic Solutions
Acidic solutions result when a salt dissolves in water and yields hydronium ions (\(H_3O^+\)) as a product of hydrolysis. This typically happens when the salt contains a cation that is the conjugate acid of a weak base.
For example, ammonium nitrate (\(NH_4NO_3\)) dissolves in water to produce ammonium ions (\(NH_4^+\)). This ammonium ion reacts with water:
For example, ammonium nitrate (\(NH_4NO_3\)) dissolves in water to produce ammonium ions (\(NH_4^+\)). This ammonium ion reacts with water:
- The ammonium ion (\(NH_4^+\)) can donate a proton to water, forming ammonia (\(NH_3\)) and hydronium ion (\(H_3O^+\)).
- The increase in hydronium ions lowers the pH of the solution.
- An acidic solution has a pH less than 7.
Basic Solutions
Basic solutions are formed when a salt yields hydroxide ions (\(OH^-\)) upon dissolving in water. These salts often consist of anions that are conjugate bases of weak acids.
Rubidium acetate (\(RbCH_3COO\)) is an example of a salt resulting in a basic solution. When dissolved, rubidium acetate dissociates into acetate ions (\(CH_3COO^-\)) which react:
Rubidium acetate (\(RbCH_3COO\)) is an example of a salt resulting in a basic solution. When dissolved, rubidium acetate dissociates into acetate ions (\(CH_3COO^-\)) which react:
- Acetate ions accept protons from water, forming acetic acid (\(CH_3COOH\)) and releasing hydroxide ions (\(OH^-\)).
- Basic solutions have a pH greater than 7.
- The solution becomes less acidic and more alkaline as hydroxide ions increase.
- The carbonate ion (\(CO_3^{2-}\)) interacts with water, producing bicarbonate (\(HCO_3^-\)) and hydroxide ions.
Neutral Solutions
Neutral solutions occur when a salt dissolves in water without changing the concentration of hydronium (\(H_3O^+\)) or hydroxide (\(OH^-\)) ions. This is common for salts derived from strong acids and strong bases.
Potassium sulfate (\(K_2SO_4\)) is one such salt that results in a neutral solution. Here's why:
Potassium sulfate (\(K_2SO_4\)) is one such salt that results in a neutral solution. Here's why:
- Neither of its ions鈥攑otassium (\(K^+\)) from a strong base (KOH) and sulfate (\(SO_4^{2-}\)) from a strong acid (H鈧係O鈧�)鈥攗ndergo significant hydrolysis.
- Neither ion substantially alters the pH when dissolved.
- Neutral aqueous solutions typically have a pH of 7.
Conjugate Acid-Base Pairs
The concept of conjugate acid-base pairs is essential in understanding salt hydrolysis. When a salt dissolves in water, it may yield ions that are conjugate acids or bases, playing crucial roles in determining the solution's pH.
A conjugate acid is formed when a base gains a proton, and a conjugate base forms when an acid loses one:
A conjugate acid is formed when a base gains a proton, and a conjugate base forms when an acid loses one:
- The strength of a conjugate acid or base affects whether a salt solution is acidic or basic.
- For instance, the ammonium ion (\(NH_4^+\)) is a conjugate acid of ammonia (\(NH_3\)), a weak base.
- It's a conjugate base of acetic acid (\(CH_3COOH\)), a weak acid, thereby affecting the solution's basicity.
- Predicting the direction of reactions in aqueous solutions.
- Determining whether a solution will be acidic, basic, or neutral based on its components.
