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Name: __________________

Reviewing the Properties of Salts In chemistry, a salt is an ionic compound that results from the neutralization reaction of an acid and a base. Salts are composed of related numbers of cations (positively charged ions) and anions (negative ions) so that the product is electrically neutral (without a net charge).

Property Example 1. Salts are compounds containing ionic bonds.

2. Most salts are soluble in water generating ions.

(Table F) Dissociation Equation

____________________________

3. _________________________ ____________________________ ____________________________

4. _________________________ ____________________________ ____________________________

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Self-Ionization of Water

This reaction can also be written as...

______________________________________________________________

Equilibrium Expression for Water H2O(l) <---> H+(aq) + OH-(aq)

At 250C, Kw = ___________________ Meaning…

[H+] = ______________ [OH-] =_______________

Comparing the [H+] and [OH-]

Acidic Solution Neutral Solution Basic Solution

=

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Name: _______________________ Station 1 Arrhenius Acids and Bases How do acids and bases behave in water?

Acids and bases play an important role in our lives. Numerous biological processes, industrial applications, and even environmental problems are a function of the acidity or basicity (alkalinity) of aqueous solutions. It is therefore important to

understand what makes a substance behave as an acid or a base when dissolved in water. What properties can be used to distinguish acids and bases? Let’s explore the characteristic features that will allow us to classify substances as acids and

bases. Answer the following questions using the chart at your station. 1. What is the common name for Vitamin C?

___________________________ Is Vitamin C classified as an acid or a base?

_______________ 2. Examine the properties of the Arrhenius acids on the chart. List three properties that all Arrhenius acids have in common.

I. _____________________________________

II. _____________________________________

III. _____________________________________

3. Examine the chemical formulas for the Arrhenius acids on the chart. What feature do all the Arrhenius acid chemical formulas (cation) have in common? (Identify the cation)

___________________________________________________ 4. Examine the properties of the Arrhenius bases on the chart. List three common properties that all Arrhenius bases have in common.

I. _____________________________________

II. _____________________________________

III. _____________________________________

5. Examine the chemical formula for the Arrhenius bases on the chart. What anion does all the Arrhenius base chemical formula have in common? (Identify the anion)

______________________________

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6. Using your glossary, define the following terms: Arrhenius Acid Arrhenius Base

7. The student dissolved a small amount of baking soda in water and tested it with litmus paper. The litmus paper turned blue. Is baking soda likely an acid or a base?

__________________ 8. Below are examples of an Arrhenius acid and base. Complete the following statements:

a. HNO3 is an Arrhenius (acid or base) ___________ and increases the concentration of (H+ or OH-)_______________ ions when added to water. b. Ca(OH)2 is an Arrhenius (acid or base) __________ and increases the concentration of (H+ or OH-) _______________ ions when added to water.

HCl ----> H+(aq) + Cl-(aq)

Acid

NaOH----> Na+(aq) + OH-(aq)

Base

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Practice Regents Questions 1. Which is a property of any solution that contains dissociated (or ionized) ions? a. is acidic b. is basic c. conducts electricity d. contains a salt 2. Which describes a solution that contains hydrogen ions as the only positive ions? a. acidic b. basic c. salted d. sugared 3. Which substance is classified as an Arrhenius acid? a. NaCl b. HCl c. LiOH d. KOH 4. Which compound is an Arrhenius base? a. CH3OH b. CHCl3 c. Ca(OH)2 d. LiNO3 5. Which property is most closely associated with a solution of any Arrhenius acid? a. only hydrogen ions in solution b. hydrogen ions as the only positive ions in solution c. only hydroxide ions in solution d. hydroxide ions as the only negative ions in solution 6. Based on the Arrhenius theory, when potassium hydroxide dissolves in water, the only negative ion in the aqueous solution is

a. O2 (aq) b. H+ (aq) c. OH2 (aq) c. OH- (aq) 7. Which compounds are classified as Arrhenius acids? a. HCl and NaOH b. HNO3 and NaCl c. NH3 and H2CO3 d. HBr and H2SO4 8. Which compounds are electrolytes? a. C2H5OH and H2SO4 (2) C2H5OH and CH4 (3) KOH and H2SO4 (4) KOH and CH4

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Name: ________________________ Station 2 :IUPAC Naming of Acids and Bases

Name the following Binary Acids: Prefix “hydro” suffix ending “ic”

Chemical Formula IUPAC Name HCl(aq)

H2Se(aq) HF(aq) HI(aq)

Name the following Ternary Acids: These acids usually contain a polyatomic ion. No Prefix! Change the suffix “ate” to “ic” Change the suffix “ite” to “ous”

Chemical Formula IUPAC Name HClO3(aq) H3PO3(aq) HNO2(aq) HNO3(aq) HMnO4(aq)

Follow the rules for naming acids and bases and research on your phone or iPad where these acids are commonly found. IUPAC Name Chemical

Formula Where Found

Acetic Acid

H2CO3(aq)

HBr(aq)

Gastric juices in stomach

H3PO4(aq)

Hydrosulfuric acid

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Name the following Bases: Name the metal + name the anion Chemical Formula

IUPAC Name

KOH CsOH Fe(OH)3 Ca(OH)2 NH4OH Name Chemical

Formula Uses

Aluminum hydroxide

Manufacture of mortar and pestle

NaOH

Magnesium Hydroxide

Check out your homework packet for more practice

in naming acids and bases ☺

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Name: ________________ Station 3: Introduction to the pH Scale

In biology and other science courses pH is introduced as a way to quantify the acidity or basicity of a solution and is related to the concentration of H3O+ ions. The letters pH

stands for the French words pouvoir hydrogen, meaning “hydrogen power” – a difference of one unit on the pH scale corresponds to a power of ten difference in the concentration

of H3O+ ions. But, what is actually being measured? We know that a pH of 7 is neutral, below 7 is acid, and above 7 is base, but why?

Complete the following table:

Acidic Solution [H+] > [OH-]

Neutral Solution [H+] = [OH-]

Basic Solution [H+] < [OH-]

In terms of pH…

In terms of pH…

In terms of pH…

List three common substances that are acids: __________________________

__________________________

__________________________

List three common substances that are neutral: __________________________

__________________________

__________________________

List three common substances that are bases: __________________________

__________________________

__________________________

1. Which substance represents the strongest acid? ____________________ 2. Which substance represents the strongest base? _______________________ 3. The pH of pancreatic juice is 7.9. Is the pancreatic juice acidic or basic? _____________ 4. A difference of one unit on the pH scale corresponds to what in terms of [H3O+]?

______________________________________________________________________________________________________________________________

Increasing Acidity Increasing Basicity

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1. Determine the hydronium and hydroxide ion concentrations in a solution that is

1 x 10-4M HCl.

[H+] ________________ [OH-] ____________________

pH=____________________

Determine the hydronium and hydroxide ion concentrations in a solution that is 1 x 10-2M NaOH. (Be Careful!)

[H+] ________________ [OH-] ____________________

pH=______________________

Determine the pH of the following solutions.

a. 1 x 10-3M HCl pH= _________ b. 1 x 10-5M HNO3 pH =_________

c. 1 x 10-4M NaOH pH =_________ d. 1 x 10-2M KOH pH =_________

Acid rain is a problem in industrialized countries around the world. Oxides of sulfur and nitrogen are formed when various fuels are burned. These oxides dissolve in atmospheric water droplets that fall to the earth as acid rain of acid snow. While normal rain has a pH between 5.0 and 6.0 due to the presence of dissolved carbon dioxide, acid rain has a pH of 4 or lower. This level of acidity can damage trees, and plants, leach minerals from the soil, and cause death of aquatic

animals, and plants. If the pH of the soil is too low, then quicklime, CaO, can be added to the soil to increase the pH. Quicklime produces calcium hydroxide when it dissolves in water.

a. A sample of soil has a pH of 4.0. After the addition of quicklime, the H+ ion concentration of the soil is 1/100 of the original H+ ion concentration of the soil. What is the new pH of the soil sample? b. Why is acid rain a danger to our environment?

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Remember: The pH scale is logarithmic- a solution of a pH 3 is ten more acidic than a

solution of pH 4, and 100 times more acidic than a solution of pH 5.

Practice Regents Questions:

4. When the pH of an aqueous solution is changed from 1 to 2, the concentration of hydronium ions in the solution is (A) decreased by a factor of 2 (C) decreased by a factor of 10

(B) increased by a factor of 2 (D) increased by a factor of 10 5. When the pH of a solution is changed from 4 to 2, the hydronium ion concentration of the solution (A) decreases by a factor of 10 (C) increases by a factor of 10 (B) decreases by a factor of 100 (D) increases by a factor of 100 6. When the hydronium ion concentration of a solution is increased by a factor of 10, the pH value of the solution

(A) decreases 1 pH unit (C) decreases 10 pH units (B) increases 1 pH unit (D) increases 10 pH units

7. Which pH value describes the most acidic solution? (A) 1 (B) 2 (C) 4 (D) 10 8. What is the pH of an aqueous solution of C6H12O6? (A) 1 (B) 7 (C) 11 (D) 14 9. Which of these 0.10M solutions has the highest pH? (A) KOH (B) C2H5OH (C) C3H5(OH)3 (D) H2SO4

Extension: How To Calculate pH

pH = -log[H+]

What is the pH of a solution if the [H+] is 3.4 x 10 -5M? Determine the pH of a 2.5 x 10-6M HNO3 solution.

Example: Calculate the pH for a specific [H+]. Calculate pH given [H+] = 1.4 x 10-5 M pH = -log[H+] pH = -log(1.4 x 10-5) pH = 4.85

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Name: _______________________

Arrhenius’ Definition of Acids and Bases In 1903 Svante Arrhenius won the Nobel Prize in Chemistry for defining

acids and bases in terms of ions produced in water.

_______________________ ________________________

Strong versus Weak Acids(Ka) Acids are substances that surround us in our everyday life. The uses of acids range from providing essential nutrients for our bodies to dissolving metals. Some acids are safe to handle with our bare hands or even use in food preparation. Other acids will severely

burn human skin. It is important to understand how these substances can all be acids and yet have such different properties.

Acids Bases Metal bonded with OH-ion

_________________

_________________

_________________

_________________

_________________ _________________ _________________

_________________

Ka

_________________

_________________ _________________

_________________ _________________ _________________

_________________

_________________

Strength

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Strong versus Weak Bases(Kb) Bases just like acids play an important role in our lives. Numerous biological processes,

industrial applications, and even environmental problems are a function of the acidity or basicity (alkalinity) of aqueous solutions.

Table F Solubility Guidelines for Aqueous Solutions

Ions That Form Insoluble Compounds

Exceptions

Hydroxide (OH-)

When combined with Group 1 ions, Ca+2, Ba+2, Sr+2, or ammonium

(NH4+)

Indicate the strength of each of the following bases. NaOH(aq) _____________________ Ba(OH)2(aq) ________________________ Al(OH)3(aq) _____________________ LiOH(aq) ________________________

Which base from Table L-Common Bases is an example of a weak base: _____________ Let’s Review: 1. Which compounds are classified as Arrhenius acids? (A) HCl and NaOH (B) HNO3 and NaCl (C) NH3 and H2CO3 (D) HBr and H2SO4

2. A substance that dissolves in water and produces hydronium ions as the only positive ions in the solution is classified as

(A) an alcohol (B) a base (C) an acid (D) a salt

3. Potassium hydroxide is classified as an Arrhenius base because KOH contains (A) OH− ions (B) K+ ions (C) O2− ions (D) H+ ions 4. Which salt is most soluble (highest Ksp) in water?

(A) PbS (B) Na2S (C) BaS (D) Fe2S3 5. The ionization constant (Ka’s) of four acids is shown below. Which represents the weakest of these acids? (A) Ka = 1.7 x 10-2 (B) Ka = 7.1 x 10-3 (C) Ka = 1.0 x 10-5 (D) Ka = 1.0 x 10-4 6. According to the Arrhenius theory, which list of compounds includes only bases? (A) KOH, NaOH, and CH3OH (C) NaOH, Ca(OH)2, and CH3COOH (B) KOH, NaOH, and LiOH (D) LiOH, Ca(OH)2, and C2H4(OH)2

7. Which group of the periodic table contains elements whose hydroxides are strong bases? (A) 1 (B) 13 (C) 15 (D) 17