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Chapter 15

Acids and Bases

Strong acids and bases are often powerful, dangerous substances. Sulfuric acid

(H2SO4) will decompose sugar into black charcoal. Nitric acid (HNO3) reacts with

many metals, and hydrochloric acid (HCl) will eat away at a penny from the inside

out. The base sodium hydroxide (NaOH) will react with grease and even human

hair, and hydrofluoric acid (HF) cannot be stored in bottles since it reacts with glass.

What makes these substances so reactive? What is the essential chemical unit of an acid or a

base? We can find the answers to these questions by taking a close look at the most abundant

chemical on earth, which also the most abundant chemical in our bodies:

Water.

What is water? If you took a liter of absolutely pure water, you would find not one substance, but

three. (Actually you would find more than that if you include isotopes, but that is another story).

The major substance is H2O which we are all familiar with, and the other two are the essential

chemical forms of acid and bases. These three exist in chemical equilibrium, which we just studied.

In this unit we will take a close look at this equilibrium and how we can conveniently measure it:

this is pH. We will perform a simple chemical assay to measure the exact acid or base composition

of any aqueous substance: titration. Finally, we will find out what gives these substances such

potent chemical reactivity.

How do we explain, measure, and neutralize acids and bases?

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Schedule

As we have done for each unit, you will begin with a discovery lab, the goal of which is to explore

the properties of the acidic and basic substances that you encounter every day. We then will hear

from the experts, and take a look at the conclusions they have drawn. By the end of this unit you

will be able to

1. Recognize common acids and bases

2. Measure the acidity and basicity of any substance using several different methods

3. Understand what an acid or base is using 2 complementary definitions

4. Determine how pH is related to acid or base concentration (L1 only)

5. Precisely measure the acidity or basicity of any substance by titration.

Lesson 1: Household acids and bases lab

Lesson 2: What is water? pH and exponents

Lesson 3: More acid/base math

Lesson 4: Neutralization

Lesson 5: Neutralization Lab

Lesson 6 Review

Lesson 7: Acid/base test

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5

6

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Name: _______________________________ Period: _____ Acids and Bases Lab 1

Household Acids and Bases

Introduction:

Many common household solutions contain acids and bases. Acid-base indicators such as litmus paper or even red cabbage juice turn different colors in acidic and basic solutions. They can, therefore, be used to show if a solution is acidic or basic. An acid turns blue litmus paper red, and a base turns red litmus paper blue (remember Blue = Basic). The acidity of a solution can be expressed using the pH scale. Acidic solutions have pH values less than 7, basic solutions have pH values greater than 7, and neutral solutions have a pH value equal to 7.

In this experiment, you will test the pH of various household substances using a pH meter, variable-range pH paper, litmus paper, and a selection of juices. Our goal is to evaluate the accuracy and precision of each technique.

Procedure:

Obtain a few drops of each solution and evaluate the acidity or basicity of each substance using

the techniques indicated. Watch carefully as your instructor demonstrates the method to use for

each assay. Data Table:

Test

Tube Solution Blue

Litmus

paper

Red

Litmus

paper

pH

Paper

(1-14)

Red Cabbage

Juice:

(draw color)

pH

meter

(0.0-

14.0)

cherry

Juice:

(draw color)

Phenol-

phthalein

(draw color)

1 Distilled Water

2

3

4

5

6

7

8

9

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Conclusions/Questions:

1. Which of the household solutions tested are acids?

2. How can you tell?

3. Order the acids by increasing pH.

Lowest pH (most acidic Highest pH (most basic)

2. Which of the solutions are bases? How can you tell? Order the bases by increasing pH.

3. Using a crayon or markers, draw a color guide for measuring the ph of a substance using your juice indicators:

Indicator juice 1: red cabbage juice

Indicator juice 2: cherry juice

Indicator juice 3: phenolphthalein

4. Can each juice indicator be used to determine the strength of acids and bases? Explain.

5. Which test method is superior overall? Why?

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

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Name_________________________ Date_________ Period________ acids and bases lab 2

Percentage of acetic acid in vinegar

by titration

Introduction

Vinegar is a mixture of acetic acid (C2H4O2) and water. Is it mostly

water, or mostly acetic acid? In this experiment we will find the

percent acetic acid in vinegar by mass.

Since acetic acid is an acid, it will react with a base. The more base it

takes to neutralize the acetic acid, the higher the concentration of

acetic acid. This principle is known as titration: Assaying the

concentration of an acid or base by neutralizing it.

Procedure

1. Fill a buret with 1M NaOH and record the initial volume:____

2. Add exactly 25 mL of vinegar and 3 drops of phenolphthalein to a

flask and place it under the buret.

3. Drip in the 1M NaOH while stirring until the solution just becomes permanently pink. Record

the final volume:_____

Total NaOH added: _____ mL (trial 1)

4. Perform a second trial

Total NaOH added: ____ mL (trial 2)

Average volume NaOH added:______________ mL

5. Calculate the Molarity of the vinegar using the titration formula:

molarity of known x liters of knownMolarity of unknown =

liters of unknown

(This equation is true only when the known and unknown react on a equimolar basis, which is true

in this case)

For this experiment we can rewrite the formula:

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(NaOH Molarity)(NaOH volume) vinegar Molarity =

vinegar volume

The NaOH Molarity as well as the vinegar and NaOH volume can be found above in bold.

Molarity of vinegar = _______ M

6. To calculate the percent acetic acid in the vinegar, we need to convert from grams to moles.,

where 60 grams of acetic acid (C2H4O2) is a mole. Here is a sample calculation starting from a 3

Molar acetic acid solution:

60 grams acetic acid 180 g acetic acid3 moles acetic acid 1 liter solution x x = = 18%

Liter solution 1 mole acetic acid 1000 grams solution 1000 g solution

Rewrite this below using your calculated acetic acid Molarity from the bottom of the previous

page, and show your cancelled units:

% CH3CO2H = _______ %

Finally, we can calculate the pH of this solution, since this is the negative log of the vinegar

Molarity. Here is a sample concentration based on a vinegar Molarity of 0.25 moles/liter:

-log .25 = 0.6; this is a strong acid.

Please return all equipment and clean your stations completely.

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Name_____________________ Period____ acids and bases lab practical

Acids and Bases: Lab Practical

___ Points

Each group will be given an unknown acid or base. Our sample number is __________

Find out

1. If it is an acid or a base

2. The pH of the solution

3. The Molarity of the solution.

Results:

1. To determine if our solution is acidic or basic, we used the following procedure:

This showed that our solution is a(n) acid/base (circle one)

2. To determine the pH of the solution we performed the following test(s):

This showed that the pH of our solution is____________ (please give your answer with

three significant figures)

3. To determine the Molarity of the solution, we used the following procedure:

This showed that we were given a _____M solution (please give your answer with three

significant figures).

Final Results: We were given sample #_____, which is a(n) acid/base (circle one) with a

pH of _____ and it is a ______M solution.

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Name Period ws15.1

Acids & Bases

Water is amphoteric, which means it has both the components or an Arrhenius acid (H+) and an

Arrhenius base (OH-). However, an aqueous solution of ammonia (NH3) has a pH of 13 and is

definitely a base, but it doesn‟t contain the hydroxide anion. Instead, it creates then hydroxide

anion when it reacts with water; here is the ionization reaction:

NH3 + H2O NH4+ + OH-

This reaction has produced ammonium hydroxide (NH4OH); by showing the ions separately we can

see what has happened. Ammonia has accepted a proton (H+). Ammonia is an example of a

Bronsted-Lowry base: a substance that accepts a proton. A Bronsted-Lowry acid is a substance

that donates a proton.

Look at the equilibrium reaction again. When bases accept protons they form conjugate acids:

NH4+ is an example of a conjugate acid. When acids lose protons they form conjugate bases: OH-

is an example of a conjugate base.

1. Summarize the two main acid-base theories in the table below.

ACID BASE

Arrhenius

Brønsted-Lowry

2. What is a conjugate base?

3. What is a conjugate acid?

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Label the acid (A), base (B), conjugate acid (CA), and conjugate base (CB) in each of the following

reactions.

Example: HCl + H2O H3O+ + Cl-

Acid base conj. acid conj. base

4. H2SO4 + NH3 HSO4- + NH4

+

____ ___ ___ ___

5. CH3CO2H + H2O H3O+ + CH3CO2

-

____ ___ ___ ___

6. CH3NH2 + H2O CH3NH3+ + OH-

____ ___ ___ ___

Give the conjugate base for each of the following Brønsted-Lowry acids.

Examples: HSO4- SO42- (to form a conjugate base remove H+)

HBr Br-

7. HI _______

8. NH4+ ________

9. H2CO3 _________

d. HNO3 ________

Give the conjugate acid for each of the following Brønsted-Lowry bases

Example: H2O: H3O+ (add H+ to form a conjugate acid)

10. OH- ____________________

11. O2–

12. CH3CO2– ________________

13. NH3 _______________________

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Ws15.2

Name: ________________________

Period: ____ Date: ___________

Chemistry: pH and pOH calculations pH + pOH = 14

Part 1: Fill in the missing information in the table below. Example: Given a pH of 1, an example would be battery acid, the pOH is 13, and the substance is an acid.

pH Example pOH ACID or BASE?

3.7

vinegar

4.8

8.3

Cow’s milk

3.0

13.0

0.9

pH of Common Items

1.0 battery acid

2.2 vinegar

2.4 lemon juice

2.6 Coca Cola

3.3 apple juice

3.4 fruit jellies

3.5 strawberries

3.7 orange juice

4.5 tomatoes

5.6 unpolluted rain

6.4 peas

6.4 butter

6.4 cow's milk

6.5 corn

7.0 maple syrup

7.0 distilled water

7.3 human blood

7.5 human saliva

8.0 egg whites

8.3 baking soda

9.2 borax

10.5 milk of magnesia

11.0 laundry ammonia

13.0 lye

13.1 Drano

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Name ___________________________ Period ___ ws15.3

Aqueous Acids and Bases – Additional Topics

1. What is this stuff? Write the chemical formula for each

NaOH ______ __________ ________ _______

2. Write the formulas for

Sulfuric acid: H2SO4

Nitric acid:___________

Acetic acid:________

Magnesium hydroxide:_________

Please know the names, formulas, and common names of the following common acids and bases:

Common name Name Formula Acid or base?

lye Sodium hydroxide NaOH

potash Potassium hydroxide KOH

fuming Sulfuric acid Oleum H2SO4

vinegar Acetic acid CH3CO2H

ammonia (Ammonia) NH3

stomach acid Hydrochloric acid HCl

Acid rain Nitric acid HNO3

lime Calcium hydroxide Ca(OH)2

Milk of magnesia Magnesium hydroxide Mg(OH)2

Also, be aware that there is a difference between a strong acid or base, and a concentrated acid

or base. A strong acid or base ionizes completely in solution. These include for example

hydrochloric acid, nitric acid, and sulfuric acid (H2SO4). Weak acids and bases such as acetic acid

or citric acid hold on to their acidic proton more tightly- they only ionize partially in solution.

If acids or bases they are diluted with a lot of water, however, they become dilute. As an

arbitrary rule, we will consider any solution of an acid or base with a concentration greater than

1M to be a concentrated acid.

Read this information carefully, then answer the questions below.

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3. Write the name for

Ca(OH)2

HBr

4. Write the chemical reaction between water and hydrofluoric acid, and identify each substance as an

acid, base, conjugate acid, and conjugate base. Circle the hydronium ion (H3O+).

5. The equilibrium constant for this reaction (surprisingly) is 6.3 x 10-4. What does that tell you about

hydrofluoric acid?

6. A 14M solution of HF would be an example of a

a. concentrated dilute acid

b. concentrated weak base

c. Concentrated weak acid

d. Dilute strong acid

7. What is the difference between an Arrhenius base and a Bronsted-Lowry Base?

8. Give an example of a dilute strong acid:

9. Write the chemical equation for the reaction between hydrochloric acid and water:

a. Identify the acid, base, conjugate acid, and conjugate base

b. Circle the hydronium ion

c. Is the water acting as an Arrhenius base of Bronsted-Lowry base?

d. Write the formula for Ka (this is the same as Keq) for this reaction.

e. Predict the value of Ka for this equilibrium.

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Name______________________________ Period________ ws15.4

Chemistry: pH and pOH calculations

We are mostly water. So is our planet. Most of our chemistry experiments use water. Thus, we

should know what water is in detail. It‟s H2O, right? Not quite. About one in every million molecules

of water is ionic, existing as H+OH-, not the polar covalently bonded H-O-H. When we add bases

like NaOH to water, the water has more OH- in it, and when we add acids like HCl the water has

more H+ in it.

A liter of pure water has 10-7 moles of H+ in it, and 10-7 moles of OH- in it. That‟s 0.0000001 moles.

A liter of battery acid, on the other hand, has 10-1 moles of H+, and 10-13 moles of OH- in it. That‟s

0.1 moles, which is a million times as many moles of H+, and a million times fewer OH- moles.

Someone came up with the bright idea of using the exponents, and “10-7 moles per liter hydrogen

ion concentration” became simply known as pH 7, where pH means “powers of hydrogen”

Since the log of 10-7 is -7, we are taking the negative log when we convert from concentration to

pH:

pH = -log [H+].

Note also that the more acidic something is, the less basic it is. In our example above, battery acid

has a hydrogen ion concentration of 10-1 moles per liter, or a pH of 1:

Battery acid (H2SO4): [H+] = 10-1M = pH 1

It also has a hydroxide ion concentration [OH-] of 10-13M, which is a pOH (“powers of hydroxide”)

of 13:

Battery acid (H2SO4): [OH-] = 10-13M = pH 13

The pH and the the pOH always add up to 14. This means that the H+ and OH- concentrations

always can be multiplied to equal 10-14M

pH + pOH = 14

[H+][OH-] = 10-14

We can summarize the relationship between concentration and pH:

pH + pOH = 14 [H+] = 10-pH

[OH-] = 10-pOH

pH = -log [H+]

pOH = -log [OH-][H+][OH-] = 10-14

Making sense of this for the first time can take time. The examples on the next page will enable

you to master these concepts.

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Use the details provided below for the first row to help fill in the table.

6.0 x 10-11

[OH-]Acid

Orange juice10.221.66 x 10-43.78

Acid or base?

ExamplepOH[H+]pH

pH + pOH = 14[H+] = 10-pH

pH>7 = basepH<7 = acid

[H+][OH-] = 10-14

Use the change sign (-) button, not the subtract button

Enter 10^-14/1.66E-4

Enter 10^-3.78Enter 14-3.78

Part 1: Fill in the missing information in the table below.

pH [H+] pOH [ OH– ]

ACID or

BASE?

Example

1. 3.78

2. 3.89 x 10–4 M

3. 5.19

4. 4.88 x 10–6 M

5. 8.46

6. 8.45 x 10–13 M

7. 2.14

8. 2.31 x 10–11 M

9. 10.91

10. 7.49 x 10–6 M

11. 9.94

12. 2.57 x 10-8

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Part 2: For each of the problems below, assume 100% dissociation.

1. A. Write the equation for the dissociation of hydrochloric acid.

B. Find the pH of a 0.00476 M hydrochloric acid solution.

2. A. Write the equation for the dissociation of sulfuric acid.

B. Find the pH of a solution that contains 3.25 g of H2SO4 dissolved in 2.75 liters of

solution.

3. A. Write the equation for the dissociation of sodium hydroxide.

B. Find the pH of a 0.000841 M solution of sodium hydroxide.

4. A. Write the equation for the dissociation of aluminum hydroxide.

B. If the pH is 9.85, what is the concentration of the aluminum hydroxide solution?

5. A. Write the equation for the dissociation of calcium hydroxide.

B. If the pH is 11.64 and you have 2.55 L of solution, how many grams of calcium

hydroxide are in the solution?

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Name: ___________________________________ Period: _____ ws15.5

Titrations

Directions: Answer each of the questions below with the correct reaction, volume or molarity for

either the acid or base in question. Use the solved examples as a guide.

Fill in the missing products or reactants:

1. HCl + _______ KCl + H2O

2. 2HF + Mg(OH)2 _________ + ___________

3. NH3 + HNO3 _____________

2. What is the molarity of a HCl solution if 43.33 mL 0.100 M KOH solution is needed to neutralize

20.00 mL of unknown solution?

3. What is the concentration of a household ammonia cleaning solution if 49.90 mL of 0.5900M HCl

is required to neutralize 25.00 mL of the ammonia solution?

4. In a titration, 33.21 mL 0.3040 M Rubidium Hydroxide solution is required to neutralize 20.00

mL HF solution. What is the molarity of the Hydrofluoric Acid solution?

5. A 35.00 mL sample of NaOH solution is titrated to an endpoint by 14.76 mL 0.4122 M HBr

solution. What is the molarity of the NaOH solution?

Example: CsOH + HBr CsBr + H2O

Example: What is the molarity of a CsOH solution if 30.0 mL of the solution is neutralized by

26.4 mL of 0.250 M HBr solution?

HBr HBrCsOH

CsOH

(molarity )(volume ) (0.250M)(26.4 mL)solution : molarity = = = 0.22M

volume (30.0 mL)Solution:

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Name ________________________________ Period ___ ws15.6

Titration: challenge problems

1. 49 mL of 0.200 M HCl is mixed with 50 mL of 0.200 M NaOH to reach the endpoint.

a. moles HCl =

b. moles NaOH =

c. [H+]

d. [OH-]

e. pOH =

f. pH =

2. 86.30 mL of an HCl solution was required to neutralize 31.75 mL of 0.150 M NaOH.

Determine the molarity of the HCl.

3. 63.15 mL of calcium hydroxide is required to titrate 18.9 mL of a 0.200 M H3PO4 solution. What

is the molarity of the basic solution?

4. How many mL of 0.160 M HClO4 are needed to titrate 35.0 mL of 0.215 M LiOH?

5. 25.0 mL of 1.00 M HCl are required to titrate a Drano solution (active ingredient NaOH). How

many moles of NaOH are present in the solution?

6. Ten grams of vinegar (dilute acetic acid, HC2H3O2), is titrated with 65.40 mL of 0.150 M NaOH.

a. What is the Molarity of the vinegar solution?

b. How many grams of acetic acid are present in a one liter of the vinegar solution?

c. How many grams of acetic acid are present in 10 grams of the vinegar solution

d. How many molecules of acetic acid are present in 10 grams of the vinegar solution?

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Name: ______________________________________ Period: _____ WS15.7

The Secrets behind the “Water into Wine” Demonstration Worksheet

We recently saw the water into wine demonstration, where

Water (colorless) Wine (pink) Martini (colorless) champagne (fizzy) milk (cloudy)

margarita (opaque pink)

To do this we hid small amounts of colorless chemicals in the original water decanter, as well as the

individual glasses:

1. Water: The water contained a few drops of phenolphthalein, a colorless liquid acid, which we can

draw as

Phenolphthalein-H

where H is the acidic proton that it will donate, as all acids do (recall the Bronsted-Lowy

definintion of an acid). So the water glass (which doesn‟t contain anything) is colorless.

2. Wine: The wine glass has a few drops of dilute NaOH in it: a strong base.

Write the resulting acid-base reaction (Hint: it is a double replacement reaction, and acids donate

protons):

Phenolphthalein-H + NaOH __________________+________________

The sodium salt of phenolphthalein (which you just drew above) is a vivid pink substance- hence the

rose wine. Thus phenolphthalein solutions are colorless in acidic pH, and pink when basic. This

makes them useful as indicators, much like pH paper.

3. Martini: A martini is colorless. How can we make our pink phenolphthalein solution colorless?

(Hint: reacting it with base made it pink).

Answer:___________________________________

For this we use sulfuric acid. Write out the products for this double replacement reaction: (Hint:

remember what acids do).

Phenolphthalein-Na+ + H2SO4 _______ + ____________

We are back to normal phenolphthalein, a colorless martini-looking liquid.

4. Champagne: Since we are back to an acidic solution (we used excess sulfuric acid), we can

generate some fizz by reacting it with baking soda. Please fill in the intermediate and final

products:

H2SO4 + NaHCO3 _________ + _________ CO2(g) + _____________

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5. Milk: Our milk glass contains some barium nitrate. Balance and write the products for this double

replacement reaction (hint: SO4 is a 2- anion, NO3 is a 1- anion):

____Na2SO4 + ____BaNO3 ______________ + _____________

At least one of these products is insoluble in water- the precipitate makes the solution look „milky”.

6. Strawberry Margarita: Finally, we hide excess strong base in the margarita glass. We‟ve got all

kinds of stuff in there now, but colorwise the phenolphthalein will dominate. Write out the reaction

again between phenolphthalein and sodium hydroxide to form our hot pink and this time still opaque

solution:

_______________ + ________________ ______________ + ____________

And that‟s the science behind the magic.

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Name____________________ Period_________ how to ace the acids and bases test

How to ace the acid-base test

In this unit we explored the properties of acids and bases. We started by getting a feel for acids

and bases by checking the pH of a number of household chemicals. We found that bases tend to be

slippery, and acids tend to be sour or bitter. We explained this by exploring two models: The

Arrhenius model and the Bronsted-Lowry model. We then applied this model to acids and bases, and

identified a dozen compounds that serve as examples of each.

We then looked at these substances quantitatively by examining the pH scale of acids and bases.

We observed that the ion concentrations in water are quite low, and that the equilibrium constant

Kw of water is 1 x 10-14 moles per liter.

Finally, we all learned a technique for precisely measuring the pH of any solution: titration.

The molecular basis of aqueous acidity involves the movement of the hydrogen cation (H+). In the

next chapter we will follow the movement of electrons between molecules, and this will serve as

the basis for understanding chemical reduction and oxidation.

To ace the acids and bases exam review all labs, worksheets, slides and notes. And pay particular

attention to the guided questions on the following pages.

Please remember to bring your calculator to this exam.

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1. Know your „vocab‟; remember for this exam you are required to know the names and formulas of

the following common acids and bases:

Hydrochloric acid Hydrobromic acid Nitric acid

Hydrofluoric acid Sulfuric acid Acetic acid

Sodium hydroxide Potassium hydroxide Magnesium hydroxide

Calcium hydroxide Sodium bicarbonate Ammonia

2. Know the meaning of the following terms:

a. Arrhenius acid

b. Arrhenius base

c. Bronsted-Lowry acid

d. Bronsted-Lowry base

e. titration

f. Strong acid

g. Strong base

h. pH

i. Acid pH

j. Base pH

k. Neutral pH

l. Conjugate acid

m. Conjugate base.

m. Neutralization reaction

n. Concentrated acid or base

o. dilute acid or base

p. 2 weak acids

q. 1 weak base

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3. Know how to use your formulas

(They will be provided on the exam; be able to know how to use them)

Kw = [H+][OH-] = 10-14

pH + pOH = 14

titration: [unknown] = (volume kwnn)(molarity known)/(volume unknown)

Example: For pH 3 solution [H+] = _____, [OH-] = _____, pOH =____, the solution is

Acidic/basic.

3. Be able to solve the problems on the worksheets:

a. acids and bases worksheet

-Be able to label the acid, base, conjugate acid, and conjugate base for common acid-base

reactions

Example 1: Write the products of the reaction of hydrofluoric acid and water, and

identify the acid, Bronsted-Lowry base, conjugate acid, conjugate base, and the

hydronium ion.

Be able to give the conjugate base for the common acids (remove H+), and the conjugate acids for the

common bases (add H+)

Example 2: list the conjugate acids of ammonia ( ), water ( ), and the chloride anion

( ). List the conjugate base of water ( ), Hydrochloric acid ( ), and the

hydrocarbonate anion HCO3- ( ). Finally, the hydroxide anion is the conjugate

_____________ of water.

b. Measuring the strength of acids worksheet (honors only)

-Be able to write the equilibrium reaction and acid ionization constant for a given acid

Example 3: What is Ka for HCl and what does the equation look like?

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-Be able to classify acids as strong or weak (>1 = strong; <1 = weak) (honors only)

Example 4. The Ka of an unknown acid is 2 x 10-5 M. This is a ______________ acid.

-Be able to identify the strongest and weakest acid from a list of Ka values (honors only)

-Be able to label acidic and basic solutions as dilute/concentrated, strong/weak, acid/base.

(honors only)

Example 5. A 3.2 M solution of hydrochloric acid is an example of a ________

___________ acid.

c. [H+] and [OH-] calculations worksheet

-Be able to use Kw to determine [H+] or [OH-]. (honors only; whole numbers for rest)

(remember, some of these will require the use of a calculator)

Example 5. For an aqueous solution, if [H+] is 2.1 x 10-4 M, then [OH-] must be _______ M.

d. pH and pOH calculations (also known as the worksheet from Hell)

-Be able to determine pH, pOH, [H+], and [OH-] when given one of those pieces of data

Example 6 : if [OH-] = 10-12 M, then the pH is ________, the [H+] is ____________, and the pOH is

________.

e. Titrations worksheet

-Be able to write out common acid-base neutralization reactions

Example 7. Write the reaction between hydrobromic acid and lithium hydroxide.

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-Be able to determine the concentration of an acid or base when titrated with a standard

solution.

Example 8: Write a procedure for titrating an unknown acid.

Example 9. 323 mL of 2.1M NaOH were required to neutralize 414 mL of an unknown acid. The

[OH-] concentration of the acid must be _______ M.

f. Polyprotic acids (honors only)

-Know the chemical formulas of sulfuric, carbonic, nitric, and boric acid

Example 10: Please give the formulas for the following acids: Sulfuric__________

-Be able to write the complete equilibrium reactions for these polyprotic acids in water

Example 11: Write the three lines that show the complete aqueous equilibria for phosphoric

acid.

1.

2.

3.