Ch.15 - Acid and Base EquilibriumSee all chapters
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Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
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Ch.10 - Molecular Shapes & Valence Bond Theory
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Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

When an acid and base undergo a neutralization reaction they form ions, which can create acidic, basic or neutral solutions. 

Acid – Base Neutralization

Cations (positive ions) can create either acidic or neutral solutions. 

Concept #1: Transition Metal Cations and Acidity.

If the transition metal within an ionic compound has a charge of +2 or higher then it creates an acidic solution. If it’s less than +2 then it creates a neutral solution and is classified as a non-significant ion. 

Concept #2: Main Group Metal Cations and Acidity.

If the main group metal within an ionic compound has a charge of +3 or higher then it creates an acidic solution. If it’s less than +3 then it creates a neutral solution and is classified as a non-significant ion. 

Concept #3: Positive Amines and Acidity.

Amines are compounds with only nitrogen or hydrogen (i,e. NH3) or with carbon, nitrogen and hydrogen (i,e. CH3NH2). Positive amines within compounds create acidic solutions. 

Anions (negative ions) can create either basic or neutral solutions. 

Concept #4: Anions and Basicity. 

To determine if an anion is basic or neutral you must add an H+ to it. If adding an H+ creates a weak acid then your negative ion is basic, but if adding an H+ creates a strong acid then your negative ion is neutral. 

Example #1: Determine if the following compound will create an acidic, basic or neutral solution: NaOCl

Example #2: Determine if the following compound will create an acidic, basic or neutral solution: PbCl4

Practice: Determine if each of the following compounds will create an acidic, basic or neutral solution.

a) LiC2H3O2   b) C6H5NH3Br

Practice: Determine if each of the following compounds will create an acidic, basic or neutral solution.

a) Co(HSO4)2           b) Sr(HSO3)2

Practice: Determine if each of the following compounds will create an acidic, basic or neutral solution.

Example #3: Determine whether each compound will become more soluble in an acidic solution.

a) NaBr                                                             b) LiCl                                                               c) KIO

Example #4: Determine the pH of a 0.50 M NH4Cl solution. The Kb of NH3 is 1.75 x 10-5

Practice: Determine the pH of a 0.55 M NaCN solution. The Ka of hydrocyanic acid, HCN, is 4.9 x 10-10.

Additional Problems
Which of the following statement is/are true? i. Addition of CsBrO4 to water will result in an acidic solution ii. Addition of Co(NO3)2 to water will result in a neutral solution. iii. Addition of SrF2 to water will result in a basic solution. A. iii only B. ii only C. i and iii D. i and ii E. ii and iii
As quickly as possible, identify the compounds below by type of acid or base. Possible types of acid or base are: strong acid, weak acid, strong base, weak base and spectator ions.    Name or Molecular Formula                                                            Type of Acid or Base  KI Na2HPO4 Copper (II) sulfate NaHSO3 K2CO3 NaHCO3
A salt is produced in the reaction between an _________ and a ______. A salt is a(n) ____________ compound in which the anion is neither _______ nor ______________. 
Identify the salts among the following compounds:  CaO, HClO4, Na2SO4, NH3, CH4, CH3NH2, Ba(OH)2, H2C2O4, H2O2, K2O, NH4Cl, Fe(OH)3, C6H6, Li3PO3.
Which of the following salts would lower the pH when dissolved in water? i. KNO3 ii. NH4Cl iii. KOCl A. i only B. ii only C. iii only D. i and iii E. ii and iii
Analyze the following salts with respect to their acid-base chemistry as directed: (1) write the cation, state whether it is acidic, basic, or essentially neutral, and explaining your reasoning; (2) write the anion, state whether it is acidic, basic, or essentially neutral, and explain your reasoning; and (3) state whether an aqueous solution of this salt would be acidic, basic, or neutral. If neither the cation or the anion is neutral,explain your reasoning for the overall solution. Do not forget to include the charges when writing the ions.   A. CoBr3 1. The cation is _______________ and it is (circle one):      acidic   basic   essentially neutral 2. The anion is _______________ and it is (circle one):       acidic   basic   essentially neutral 3. An aqueous solution of this salt will be (circle one):          acidic    basic   essentially neutral   B. NH4BrO   1. The cation is _______________ and it is (circle one):     acidic     basic   essentially neutral   2. The anion is _______________ and it is (circle one):      acidic     basic   essentially neutral   3. An aqueous solution of this salt will be (circle one):         acidic     basic   essentially neutral C. NaHSe   1. The cation is _______________ and it is (circle one):      acidic    basic    essentially neutral   2. The anion is _______________ and it is (circle one):       acidic     basic    essentially neutral  3. An aqueous solution of this salt will be (circle one):          acidic     basic   essentially neutral
SALT CLASSIFICATIONS When an acid neutralizes a base an ionic compound called a _______________ is formed. These solutions can be neutral, acidic or basic, depending on the acid-base properties of the cations and anions formed.  CATIONS (POSITIVE IONS) 1)  Transition Metals: If your transition metal has a charge of +2 or higher it is acidic. If the charge is less than +2 then it is neutral.      EX:   2)  Main-Group Metals: If your main-group metal has a charge of +3 or higher it is acidic. If the charge is less than +3 then it is neutral.     EX:   3)  Positive Amines  are acidic.     EX:     ANIONS (NEGATIVE IONS) 1)  NEGATIVE ION: If you have a negative ion then add an H + to it. If you create a weak acid then your negative ion is basic and if you create a strong acid then it is neutral.       EX:
Which of the following statement(s) is/are correct? i. a solution of Ca(ClO4)2 would be neutral. ii. a solution of KH, would be acidic iii. solution of NaBrO2 would be basic. A. i only B. ii only C. iii only D. i and ii E. i and iii
Which of the following would describe a solution of the salt NH  4BrO dissolved in water? Ka (HBrO) = 2.8 * 10 -9 ; Kb (NH3 ) = 1.76 * 10 -5 A) Acidic B) Basic C) Neutral D) Can’t Tell
How many of the following will form a basic solution in water? KF     NH 4Br     NaCl     KOH A) 0 B) 1 C) 2 D) 3 E) 4
The solubility of all except which one of the following salts increases as the solution pH decreases? (a) CaF2(s) (b) Na2CO3(s) (c) PbSO3(s) (d) CuS(s) (e) AgClO4(s)
Indicate whether the following salts are acidic, basic, or neutral, and write balanced chemical equations to justify your answer.
For H3PO4, Ka1 = 7.5 x 10-3, Ka2 = 6.2 x 10-8, and Ka3 = 4.2 x 10-13. An aqueous solution of NaH2PO4 therefore would be A) neutral. B) basic. C) acidic. D) a salt. E) none of the above.
A small amount of sugar completely dissolves in a beaker containing 500 mL of water and a small amount of NaCl completely dissolves in a different beaker of 500 mL water. The water then slowly evaporates. Which statement is TRUE during the evaporation?   a) The pH changes for both solutions b) The conductivity changes for both solutions c) The concentration changes for both solutions d) The NaCl solution becomes more concentrated, the sugar solution does not e) The sugar breaks down into C, H, and O atoms
Consider the ionization constants hypochlorous acid (HOCl):  Ka = 3.5 × 10−8 ; ammonia (NH3) : Kb = 1.8×10−5 . A solution of ammonium hypochlorite (NH 4OCl) is 1. neutral, because the cation and the anion in the salt hydrolyze to the same extent. 2. acidic, because the cation in the salt hydrolyzes to a greater extent than the anion in the salt. 3. neutral, because NH4OCl is a weak base/weak acid salt. 4. basic, because the anion in the salt hydrolyzes to a greater extent than the cation in the salt. 5. acidic, because the anion in the salt hydrolyzes to a greater extent than the cation in the salt. 6. basic, because the cation in the salt hydrolyzes to a greater extent than the anion in the salt.
Which of the following salts will be substantially more soluble in acidic solution than in pure water? Cu3(PO4)2          Ag 2CO3          CrBr 3          SnS          Pb(NO 3) 2   a) one of them b) two of them c) three of them d) four of them e) all of them
The solubility of which salt increases as the pH of the solution decreases? a. Ca(ClO2)2 b. Ca(NO2)2 c. Ca(SO3)2  d. Both a and c e. All of the above
Identify the pH of each salt in solution (acidic, neutral or basic). potassium chloride barium fluoride lithium bromide calcium hydroxide silver nitrate ammonium iodide sodium bisulfate silver oxide
Which ion would you expect to produce a more acidic aqueous solution: Be2+ or Ba2+ ?
Determine if each salt will form a solution that is acidic, basic, or pH neutral. (a) FeCl3   (b) NaF   (c) CaBr 2   (d) NH4Br   (e) C6H5NH3NO2   (f) KI Ka (C6H5NH3+) = 2.56 × 10 -4 Ka (HNO2) = 4.6 × 10 -4
Five aqueous solutions of the compounds below were prepared, all with the same molar concentrations, and their pH values were measured. The measured values were pH = 1.0, pH = 4.3, pH = 7.0, pH = 8.1, and pH = 13. Match the aqueous solution to the appropriate pH.
Determine if each salt will form a solution that is acidic, basic, or pH neutral. (a) SrCl2   (b) NaCHO2   (c) AlBr3   (d) NH4F   (e) CH3NH3NO3   (f) Ca(NO3)2   (g) NaClO Kb (NH3) = 1.76 × 10-5 Ka (HF) = 3.5 × 10-4
Classify these salts as acidic, basic, or neutral. NH4ClO4           NaF           LiNO 3           KCl           K 2CO3
What is the pH relevant reaction for NaF dissolved in water? A. Na+ (aq) + 2 H2O (l) → NaOH (aq) + H 3O+ (aq) B. NaF (aq) + H 2O (l) → NaOH (aq) + HF (aq) C. NaF (aq) → HF (aq) + NaOH (aq) D. Na− (aq) + H2O (l) → NaH (aq) + OH − (aq) E. F− (aq) + H2O (l) → HF (aq) + OH − (aq)
Determine if the following compound will create an acidic, basic or neutral solution. NaHSO3
Which statement below best describes the pH of an aqueous solution containing the salt CuCl2? a) The pH is acidic b) The pH is neutral c) The pH is basic d) All of the above e) None of the above
Determine if the following compound will create an acidic, basic or neutral solution. V(BrO3)3
Determine if the following compound will create an acidic, basic or neutral solution. AgBr
Determine if the following compound will create an acidic, basic or neutral solution. CuCH2ClCO2
Determine if the following compound will create an acidic, basic or neutral solution. C6H5NH3Br
Which of the following is a correct description for NH 4COOH dissolved in water? A. acidic B. basic C. neutral
What are the primary products of the neutralization reaction between an acid and a base? A. H2O and salt B. CO2 and H2O C. CO2 and protons D. H2O and hydroxide ions
Which of the following will be more soluble in an acidic solution than in pure water?a) Be(OH)2b) AgClc) CuCNd) KClO4e) SrSO4
Which aqueous solution is expected to have a pH less than 7?a. RbC2H3O2(aq)b. NH4Br(aq)c. LiNO3(aq)d. MgCl2(aq)
Which salts will be more soluble in an acidic solution than in pure water? a. CuBr b. Ag2SO4 c. BaSO3 d. Sn(OH)2 e. KClO4
Predict whether aqueous solutions of the following substances are acidic, basic, or neutral.NaClONaBr [CH3NH3]NO3AlCl3Na2SO3
A solution is prepared by adding 0.10 mol of sodium fluoride, NaF, to 1.00 L of water. Which statement about the solution is correct? A) The solution is basic. B) The solution is neutral. C) The solution is acidic. D) The concentrations of fluoride ions and sodium ions will be identical. E) The concentration of fluoride ions will be greater than the concentration of sodium ions.
Which of the following salts, when dissolved in water, produces a solution that is neutral.i. KIii. KBriii. KCliv. KF
Which one of the following is a basic salt?a. NaClb. NH4Clc. KFd. a, b, and c are all acidice. a, b, and c are all basic
Which one of these salts will form an acidic solution upon dissolving in water? A) LiBr B) NaF C) NH4Br D) KOH E) NaCN
Classify each salt as acidic, basic, or neutral. KNO3, NH4Cl, NaHCO3
Identify the following salts as neutral, acidic, or basic? SrBr2, LiF, NH4CN, LiNO3, KCN, NH4ClO4, NH4Br
A solution is prepared by adding 0.10 mol of potassium chloride, KCl, to 1.00 L of water. Which statement about the solution is correct? A) The solution is basic. B) The solution is neutral. C) The solution is acidic. D) One needs to know the temperature before any of the above predictions can be made.
What is the molarity of NO 3- in each solution? A) 0.190 M KNO3. B) 0.300 M Ca(NO3)2. C) 0.400 M Al(NO3)3.
Are the following acidic, basic or pH-neutral?a. FeCl3b. C5H5NHFc. KClO2d. NH4Cle. CaBr2
When the following reaction occurs: H3PO4(aq) + Ca(OH)2(aq) → What is the formula for the salt formed? Express your answer as a chemical formula.
Which of the following is the most basic in aqueous solution?  a) KCClH2COO b) NH4Cl c) KHSO4 d) NaBr e) KCH3COO
Identify the effect of increasing acidity on the solubility of the given compounds. The option are: increase in solubility or no change solubility. SrCO3 Ca(OH)2 NaI PbBr2  
Identify the effect of increasing acidity on the solubility of the given compounds. Place the appropriate items to their respective bins.
Which compound is more soluble in an acidic solution than in a neutral solution?a. AgClb. HgBr2 c. BaCO3d. PbI2
Identify the effect of increasing acidity on the solubility of the given compounds. CaCo3, Ca(OH)2, CuS, Ca3(PO4)2, MgBr2, NaCI 
Which salts will be more soluble in an acidic solution than in pure water?
Is an aqueous solution of CH3NH3Br acidic, basic or neutral
Identify the effect of increasing acidity on the solubility of the given compounds. Drag the appropriate items to their respective bins. BaCO3, Sr(OH)2, NiBr2, AgI, FeS
When potassium chromate, K2CrO4, dissolves in water, what ions are produced?
What is the pH relevant reaction for NaF dissolved in water? A) Na + (aq) + 2 H2O (l) → NaOH + (aq) H3O + (aq) B) NaF (aq) + H2O (l) → NaOH (aq) + HF (aq) C) NaF (aq) → HF (aq) + NaOH (aq) D) Na - (aq) + H2O (l) → NaH (aq) + OH - (aq) E) F - (aq) + H2O (l) → HF (aq) + OH - (aq)
Classify each salt as acidic, basic, or neutral. BaBr2 CH3NH3NO3 LiCN
Which of the following salts will be more soluble in acidic solution than pure water? i. BaCO3 ii. AgCl iii. PbI2. iv. Mg(OH)2.
Classify each of the following anions as basic or neutral.NO3-, F-, I-, C7H5O2-
Determine whether each of the following cations is acidic or pH-neutral.NH4+, Na+, Co3+, CH3NH3+
What salt is produced in the following reaction?HNO3(aq) + KOH(aq) → H2O(l) + ?
What salt is produced in the following reaction?HNO3(aq) + Ca(OH)2(aq) → H2O(l) + ?
What salt is produced in the following reaction?HCl(aq) + Ca(OH)2(aq) → H2O(l) + ?
What salt is produced in the following reaction?HCl(aq) + KOH(aq) → H2O(l) + ?
What is the concentration of K+ in 0.15 M of K2S ?
Why does the addition of acid increase the solubility of calcium phosphate?a. It decreases the phosphate ion concentration, forcing the equilibrium to the right.b. It increases the phosphate ion concentration, forcing the equilibrium to the right.c. It decreases the phosphate ion concentration, forcing the equilibrium to the left.d. It increases the phosphate ion concentration, forcing equilibrium to the left.e. It decreases the calcium ion concentration, forcing the equilibrium to the right.f. It increases the calcium ion concentration, forcing the equilibrium to the right.g. It decreases the calcium ion concentration, forcing the equilibrium to the left.h. It increases the calcium ion concentration, forcing equilibrium to the left.
Calculate the pH of an aqueous 0.10 M NH4Cl solution. The Kb for NH3 (ammonia) is 1.76 × 10-5.
Identify the following salts as neutral, acidic, or basic. LiF, NH4Br, LiNO3, SrBr2, KCN, NH4ClO4, NH4CN
What salt is produced in each of the following neutralization reactions?a. HNO3(aq) + KOH(aq) → H 2O(l) + ?b. HNO3(aq) + Ca(OH)2(aq) → H2O(l) + ?c. HCl(aq) + Ca(OH)2(aq) → H2O(l) + ?d. HCl(aq) + KOH(aq) → H 2O(l) + ?
All salts are ions, but not all ions are salts. This statement isa. True b. False
if CaCl2  is dissolved in water, what can be said about the concentration of the Ca 2+ ion?
Classify these salts as acidic, basic, or neutral. Na2S, KCl, LiClO4, NH4ClO4, K2CO3
Calculate the pH of a 0.250 M NH 4F aqueous solution. The Kb (NH3) = 1.76 × 10 -5 Ka (HF) = 3.5 × 10-4.
Classify these salts as acidic, basic, or neutral. NH4ClO4, NaF, LiNO3, KCI, K2CO3
Classify these salts as acidic, basic, or neutral: NH4Br, LiNO3, K2SO3, KCL, Na2S
0.1 mol of NH4CH3COO are dissolved in 1 Liter of water.   Is the solution acidic, basic, or neutral?   Note, Kb (CH3COO-) = 5.73 x 10-10 ) and    Kb, ammonia  = 1.8 *10-5). Nearly neutralImpossible to determineSubstantially acidicSubstantially basic
Determine the pH of each of the following solutions. Express your answer to two decimal places. 0.19 M NH4Cl 0.15 M NaC2H3O2 0.13 M NaCl
Determine the pH of each of the following solutions. a. .15 M KCHO2 b. .19 M CH3NH3I c. .17 M KI
The addition of which of the following substances will not affect the existing equilibrium in a HF solution?a. KFb. HClc. NaOHd. KCl 
What is the pH of a 0.100M solution of potassium bicarbonate?
Classify these salts as acidic, basic, or neutral. a. K2SO3 b. Na2S c. KCl d. LiBr e. NH4Br
Classify each salt as acidic, basic, or neutral Drag the appropriate items to their respective bins.
Consider this aqueous reaction. HNO3 (aq) + Ba(OH)2(aq) →What is the formula for the salt that forms?
Classify these salts as acidic, basic or neutral.  
Which ion forms a basic solution when dissolved in water?
The pH of an aqueous solution of 8.86 times 10-2 M sodium cyanide, NaCN (aq), is This solution is 
Which of the following compounds is a strong electrolyte? (i) HF (ii) CH3CH2OH (iii) CH3OH(iv) NaF (e) H2O
What salt is formed in the reaction of zinc with nitric acid? Write the formula of the salt. Select the name of the salt. 
Which of the following will be more soluble in an acidic solution than in pure waterBe(OH)2AgClCuCNKClO4SrSO4
Identify the following salts as neutral acidic or basic:i) LiNO3ii) SrBr2iii) LiF iv) KCN v) NH4ClO4vi) NH4Brvii) NH4CNPlease include why are they neutral basic or acidic.