Introductory Chemistry: A Foundation - Zumdahl S.S., DeCoste D.J. 2019

Chapter Review

Key Terms

· matter (3.1)

· states of matter (3.1)

· solid (3.1)

· liquid (3.1)

· gas (3.1)

· physical properties (3.2)

· chemical properties (3.2)

· physical change (3.2)

· chemical change (3.2)

· reaction (3.2)

· element (3.3)

· compound (3.3)

· mixture (3.4)

· pure substance (3.4)

· homogeneous mixture (3.4)

· solution (3.4)

· heterogeneous mixture (3.4)

· distillation (3.5)

· filtration (3.5)

For Review

· Matter has mass and occupies space. It is composed of tiny particles called atoms.

· Matter exists in three states:

o Solid—is a rigid substance with a definite shape

o Liquid—has a definite volume but takes the shape of its container

o Gas—takes the shape and volume of its container

· Matter has both physical and chemical properties.

o Chemical properties describe a substance’s ability to change to a different substance.

o Physical properties are the characteristics of a substance that do not involve changing to another substance.

§ Examples are shape, size, and color.

· Matter undergoes physical and chemical changes.

o A physical change involves a change in one or more physical properties but no change in composition.

o A chemical change transforms a substance into one or more new substances.

· Elements contain only one kind of atom—elemental copper contains only copper atoms, and elemental gold contains only gold atoms.

· Compounds are substances that contain two or more kinds of atoms.

· Compounds often contain discrete molecules.

· A molecule contains atoms bound together in a particular way—an example is Icon , the water molecule, which is written .

· Matter can be classified as a mixture or a pure substance.

o A mixture has variable composition.

§ A homogeneous mixture has the same properties throughout.

§ A heterogeneous mixture has different properties in different parts of the mixture.

o A pure substance always has the same composition.

· Mixtures can be separated into pure substances by various means including distillation and filtration.

· Pure substances are of two types:

o Elements, which cannot be broken down chemically into simpler substances

o Compounds, which can be broken down chemically into elements

Active Learning Questions

These questions are designed to be considered by groups of students in class. Often these questions work well for introducing a particular topic in class.

· 1.

When water boils, you can see bubbles rising to the surface of the water. Of what are these bubbles made?

a. air

b. hydrogen and oxygen gas

c. oxygen gas

d. water vapor

e. carbon dioxide gas

· 2.

If you place a glass rod over a burning candle, the glass turns black. What is happening to each of the following (physical change, chemical change, both, or neither) as the candle burns? Explain.

a. the wax

b. the wick

c. the glass rod

· 3.

The boiling of water is a

a. physical change because the water disappears.

b. physical change because the gaseous water is chemically the same as the liquid.

c. chemical change because heat is needed for the process to occur.

d. chemical change because hydrogen and oxygen gases are formed from water.

e. chemical and physical change.

Explain your answer.

· 4.

Is there a difference between a homogeneous mixture of hydrogen and oxygen in a ratio and a sample of water vapor? Explain.

· 5.

Sketch a magnified view (showing atoms and/or molecules) of each of the following, and explain why the specified type of mixture is

a. a heterogeneous mixture of two different compounds.

b. a homogeneous mixture of an element and a compound.

· 6.

Are all physical changes accompanied by chemical changes? Are all chemical changes accompanied by physical changes? Explain.

· 7.

Why would a chemist find fault with the phrase “pure orange juice”?

· 8.

Are separations of mixtures physical or chemical changes? Explain.

· 9.

Explain the terms element, atom, and compound. Provide an example and microscopic drawing of each.

· 10.

Mixtures can be classified as either homogeneous or heterogeneous. Compounds cannot be classified in this way. Why not? In your answer, explain what is meant by heterogeneous and homogeneous.

· 11.

Provide microscopic drawings down to the atoms for Fig. 3.10 in your text.

· 12.

Look at Table 2.8 in your text. How do the densities of gases, liquids, and solids compare with one another? Use microscopic pictures to explain why this is true.

· 13.

Label each of the following as an atomic element, a molecular element, or a compound.

A set of seven illustrations are shown. The first illustration shows a gray sphere is bonded to two red spheres on either side. The second illustration shows a red sphere bonded to two blue spheres on either side. The third illustration shows two identical blue spheres bonded together. The fourth illustration shows a green sphere. The fifth illustration shows two identical red spheres bonded together. The sixth illustration shows two identical red spheres bonded together, each of which are bonded to a blue sphere. The seventh illustration shows a yellow sphere.

· 14.

Match each description below with the following microscopic pictures. More than one picture may fit each description. A picture may be used more than once or not used at all.

A set of six illustrations show different types of matter. Illustration 1 shows five identical diatomic molecules. Illustration 2 shows diatomic molecules of two different types, one represented by two blue spheres, and the other represented by a blue sphere bonded to an orange sphere. Illustration 3 shows molecules of two different types, one of them diatomic consisting of a blue sphere and an orange sphere, and the other monoatomic, consisting only of a blue sphere. Illustration 4 shows 3 identical diatomic molecules represented by a blue sphere bonded to an orange sphere. Illustration 5 shows two rows of closely packed, identical atoms represented by blue spheres. Illustration 6 shows six atoms, three represented by blue spheres and the other three by orange spheres.

a. a gaseous compound

b. a mixture of two gaseous elements

c. a solid element

d. a mixture of gaseous element and a gaseous compound

Questions and Problems: 3.1 Matter

Questions and Problems with answers below also have full solutions in the Student Solutions Guide.


· 1.

What are the two characteristic properties of matter?

· 2.

What is the chief factor that determines the physical state of a sample of matter?

· 3.

Of the three states of matter, and are not very compressible.

· 4.

has a definite volume but takes the shape of its container.

· 5.

Compare and contrast the ease with which molecules are able to move relative to each other in the three states of matter.

· 6.

Matter in the state has no shape and fills completely whatever container holds it.

· 7.

What similarities are there between the solid and liquid states of matter? What differences are there between these two states?

· 8.

A sample of matter that is “rigid” has (stronger/weaker) forces among the particles in the sample than does a sample that is not rigid.

· 9.

Consider three -g samples of water: one as ice, one as liquid, and one as vapor. How do the volumes of these three samples compare with one another? How is this difference in volume related to the physical state involved?

· 10.

In a sample of a gaseous substance, more than of the overall volume of the sample is empty space. How is this fact reflected in the properties of a gaseous substance compared with the properties of a liquid or solid substance?

Questions and Problems: 3.2 Physical and Chemical Properties and Changes

Questions and Problems with answers below also have full solutions in the Student Solutions Guide.


· 11.

Elemental bromine is a dense, dark-red, pungent-smelling liquid. Are these characteristics of elemental bromine physical or chemical properties?

· 12.

Is the process represented below a physical or chemical change?

An illustration uses space-filling models to show the decomposition of two water molecules into two molecules of hydrogen and one molecule of oxygen when electric current is passed through them. Each water molecule is composed of an atom of oxygen, represented by a red sphere, and two atoms of hydrogen, represented by blue spheres, which are bound to the oxygen. The component elements are shown as a diatomic molecule of oxygen, represented by two red spheres, and two diatomic molecules of hydrogen, represented by two blue spheres each.

(For Exercises 13—14) Magnesium metal is very malleable and is able to be pounded and stretched into long, thin, narrow “ribbons” that are often used in the introductory chemistry lab as a source of the metal. If a strip of magnesium ribbon is ignited in a Bunsen burner flame, the magnesium burns brightly and produces a quantity of white magnesium oxide powder.

· 13.

From the information given above, indicate one chemical property of magnesium metal.

· 14.

From the information given above, indicate one physical property of magnesium metal.

· 15.

You want to cook some raw noodles to make a pasta dish for supper. So, you turn on the gas stovetop (which uses a flame), place a large pot of water over the flame, wait for the water to boil, place the noodles in the boiling water for minutes, and then drain the water from the noodles. Identify one example of a physical change and one example of a chemical change in this process. Explain your answer for each.

· 16.

Which of the following is/are examples of a chemical change?

a. carving wood

b. snow melting

c. dry ice subliming (solid vaporizing into a gas, passing the liquid state)

d. burning cookies in the oven

· 17.

Classify each of the following as a physical or chemical change or property.

a. Oven cleaners contain sodium hydroxide, which converts the grease/oil spatters inside the oven to water-soluble materials, which can be washed away.

b. A rubber band stretches when you pull on it.

c. A cast-iron frying pan will rust if it is not dried after washing.

d. Concentrated hydrochloric acid has a choking, pungent odor.

e. Concentrated hydrochloric acid will burn a hole in cotton jeans because the acid breaks down the cellulose fibers in cotton.

f. Copper compounds often form beautiful blue crystals when a solution of a given copper compound is evaporated slowly.

g. Copper metal combines with substances in the air to form a green “patina” that protects the copper from further reaction.

h. Bread turns brown when you heat it in a toaster.

i. When you use the perfume your boyfriend gave you for your birthday, the liquid of the perfume evaporates quickly from your skin.

j. If you leave your steak on the gas grill too long, the steak will turn black and char.

k. Hydrogen peroxide fizzes when it is applied to a cut or scrape.

· 18.

Classify each of the following as a physical or chemical change or property.

a. A fireplace poker glows red when you heat it in the fire.

b. A marshmallow turns black when toasted too long in a campfire.

c. Hydrogen peroxide dental strips will make your teeth whiter.

d. If you wash your jeans with chlorine bleach, they will fade.

e. If you spill some nail polish remover on your skin, it will evaporate quickly.

f. When making ice cream at home, salt is added to lower the temperature of the ice being used to freeze the mixture.

g. A hair clog in your bathroom sink drain can be cleared with drain cleaner.

h. The perfume your boyfriend gave you for your birthday smells like flowers.

i. Mothballs pass directly into the gaseous state in your closet without first melting.

j. A log of wood is chopped up with an axe into smaller pieces of wood.

k. A log of wood is burned in a fireplace.

Questions and Problems: 3.3 Elements and Compounds

Questions and Problems with answers below also have full solutions in the Student Solutions Guide.


· 19.

Although some elements are found in an isolated state, most elements are found combined as with other elements.

· 20.

What is a compound? What are compounds composed of? What is true about the composition of a compound, no matter where we happen to find the compound?

· 21.

Certain elements have special affinities for other elements. This causes them to bind together in special ways to form .

· 22.

can be broken down into the component elements by chemical changes.

· 23.

The composition of a given pure compound is always no matter what the source of the compound.

· 24.

Which of the following are considered compounds (as opposed to elements)?





Questions and Problems: 3.4 Mixtures and Pure Substances

Questions and Problems with answers below also have full solutions in the Student Solutions Guide.


Icon directs you to the Chemistry in Focus feature in the chapter

· 25.

If iron filings are placed with excess powdered sulfur in a beaker, the iron filings are still attracted by a magnet and could be separated from the sulfur with the magnet. Would this combination of iron and sulfur represent a mixture or a pure substance?

· 26.

If the combination of iron filings and sulfur in Question 25 is heated strongly, the iron reacts with the sulfur to form a solid that is no longer attracted by the magnet. Would this still represent a “mixture”? Why or why not?

· 27.

What does it mean to say that a solution is a homogeneous mixture?

· 28.

Which of the following substances is(are) homogeneous mixture(s)?

a. chocolate chip cookie

b. iodine crystals

c. air (in this room)

d. gasoline (for a car)

e. sucrose, (commonly found in table sugar)

· 29.

Classify the following as mixtures or pure substances.

a. the vegetable soup you had for lunch

b. the fertilizer your dad spreads on the front lawn in the spring

c. the salt you sprinkle on your French fries

d. the hydrogen peroxide you cleaned a cut finger with

· 30.

Classify the following as mixtures or pure substances.

a. a multivitamin tablet

b. the blue liquid in your car’s windshield reservoir

c. a ham and cheese omelet

d. a diamond

· 31.

Classify the following mixtures as heterogeneous or homogeneous.

a. soil

b. mayonnaise

c. Italian salad dressing

d. the wood from which the desk you are studying on is made

e. sand at the beach

· 32.

Icon Read the “Chemistry in Focus” segment Concrete—An Ancient Material Made New and classify concrete as an element, a mixture, or a compound. Defend your answer.

Questions and Problems: 3.5 Separation of Mixtures

Questions and Problems with answers below also have full solutions in the Student Solutions Guide.


· 33.

Describe how the process of distillation could be used to separate a solution into its component substances. Give an example.

· 34.

Describe how the process of filtration could be used to separate a mixture into its components. Give an example.

· 35.

In a common laboratory experiment in general chemistry, students are asked to determine the relative amounts of benzoic acid and charcoal in a solid mixture. Benzoic acid is relatively soluble in hot water, but charcoal is not. Devise a method for separating the two components of this mixture.

· 36.

During a filtration or distillation experiment, we separate a mixture into its individual components. Do the chemical identities of the components of the mixture change during such a process? Explain.

Additional Problems

· 37.

If powdered elemental zinc and powdered elemental sulfur are poured into a metal beaker and then heated strongly, a very vigorous chemical reaction takes place, and the zinc sulfide is formed.

· 38.

Classify each of the following as a(n) element, compound, pure substance, homogeneous mixture, and/or heterogeneous mixture. More than one classification is possible, and not all of them may be used.

a. calcium carbonate

b. iron

c. water you regularly drink (from your faucet or a bottle)

· 39.

If a piece of hard, white blackboard chalk is heated strongly in a flame, the mass of the piece of chalk will decrease, and eventually the chalk will crumble into a fine white dust. Does this change suggest that the chalk is composed of an element or a compound?

· 40.

During a very cold winter, the temperature may remain below freezing for extended periods. However, fallen snow can still disappear, even though it cannot melt. This is possible because a solid can vaporize directly, without passing through the liquid state. Is this process (sublimation) a physical or a chemical change?

· 41.

Discuss the similarities and differences between a liquid and a gas.

· 42.

True or false? Salad dressing (such as oil and vinegar dressing) separating into layers after standing is an example of a chemical change because the end result looks different from how it started. Explain your answer.

o True

o False

· 43.

The fact that solutions of potassium chromate are bright yellow is an example of a property.

· 44.

Which of the following are true?

a. is considered a compound.

b. Metal rusting on a car is a chemical change.

c. Dissolving sugar in water is a chemical change.

d. Sodium chloride is a homogeneous mixture.

(For Exercises 45—46) Solutions containing nickel(II) ion are usually bright green in color. When potassium hydroxide is added to such a nickel(II) solution, a pale-green fluffy solid forms and settles out of the solution.

· 45.

The fact that a reaction takes place when potassium hydroxide is added to a solution of nickel(II) ions is an example of a property.

· 46.

The fact that a solution of nickel(II) ion is bright green is an example of a property.

· 47.

The processes of melting and evaporation involve changes in the of a substance.

· 48.

A(n) always has the same composition.

· 49.

Classify each of the following as a physical or chemical change or property.

a. Milk curdles if a few drops of lemon juice are added to it.

b. Butter turns rancid if it is left exposed at room temperature.

c. Salad dressing separates into layers after standing.

d. Milk of magnesia neutralizes stomach acid.

e. The steel in a car has rust spots.

f. A person is asphyxiated by breathing carbon monoxide.

g. Sulfuric acid spilled on a laboratory notebook page causes the paper to char and disintegrate.

h. Sweat cools the body as the sweat evaporates from the skin.

i. Aspirin reduces fever.

j. Oil feels slippery.

k. Alcohol burns, forming carbon dioxide and water.

· 50.

Which of the following contains an element, a compound, and a mixture?

a. copper, silicon dioxide , copper(II) sulfate

b. hydrogen, carbon dioxide , water

c. chili, pizza, steak

d. sodium, sodium chloride , salt water

e. nitrogen, argon, air

· 51.

Classify the following mixtures as homogeneous or heterogeneous.

a. potting soil

b. white wine

c. your sock drawer

d. window glass

e. granite

· 52.

Which of the following best describes the air around you on a typical day? (Assume the air is made up of nitrogen and oxygen. Ignore other gases such as water vapor and carbon dioxide.).

a. Air is a homogeneous mixture of gases because it generally contains the same ratio of gaseous substances from one region to another.

b. Air is a heterogeneous mixture of gases because it contains different gaseous substances in unequal amounts.

c. Air is a pure substance because it always has the same composition.

d. Air is a compound because it is made up of nitrogen and oxygen, which are different elements.

e. Air is an element because it contains nitrogen and oxygen, which are found in the periodic table.

· 53.

Give three examples each of heterogeneous mixtures and homogeneous mixtures.

· 54.

True or false? Mixtures always result in a chemical reaction because they consist of two or more substances and thus combine to create a new product.

o True

o False

· 55.

Choose an element or compound with which you are familiar in everyday life. Give two physical properties and two chemical properties of your choice of element or compound.

· 56.

Oxygen forms molecules in which there are two oxygen atoms, . Phosphorus forms molecules in which there are four phosphorus atoms, . Does this mean that and are “compounds” because they contain multiple atoms? and react with each other to form diphosphorus pentoxide, . Is a “compound”? Why (or why not)?

· 57.

Give an example of each of the following:

a. a heterogeneous mixture

b. a homogeneous mixture

c. an element

d. a compound

e. a physical property or change

f. a chemical property or change

g. a solution

· 58.

Distillation and filtration are important methods for separating the components of mixtures. Suppose we had a mixture of sand, salt, and water. Describe how filtration and distillation could be used sequentially to separate this mixture into the three separate components.

· 59.

Sketch the apparatus commonly used for simple distillation in the laboratory, identifying each component.

· 60.

The properties of a compound are often very different from the properties of the elements making up the compound. Water is an excellent example of this idea. Discuss.

· 61.

Which of the following best describes the substance ?

a. element

b. compound

c. heterogeneous mixture

d. homogeneous mixture

ChemWork Problems

These multiconcept problems (and additional ones) are found interactively online with the same type of assistance a student would get from an instructor.

· 62.

Which of the following statements is(are) true?

a. A spoonful of sugar is a mixture.

b. Only elements are pure substances.

c. Air is a mixture of gases.

d. Gasoline is a pure substance.

e. Compounds can be broken down only by chemical means.

· 63.

Which of the following describes a chemical property?

a. The density of iron is .

b. A platinum wire glows red when heated.

c. An iron bar rusts.

d. Aluminum is a silver-colored metal.

· 64.

Which of the following describes a physical change?

a. Paper is torn into several smaller pieces.

b. Two clear solutions are mixed together to produce a yellow solid.

c. A match burns in the air.

d. Sugar is dissolved in water.

Chapters 1-3. Cumulative Review


Questions with answers below also have full solutions in the Student Solutions Guide.

· 1.

In the exercises for Chapter 1 of this text, you were asked to give your own definition of what chemistry represents. After having completed a few more chapters in this book, has your definition changed? Do you have a better appreciation for what chemists do? Explain.

· 2.

Early on in this text, some aspects of the best way to go about learning chemistry were presented. In beginning your study of chemistry, you may initially have approached studying chemistry as you would any of your other academic subjects (taking notes in class, reading the text, memorizing facts, and so on). Discuss why the ability to sort through and analyze facts and the ability to propose and solve problems are so much more important in learning chemistry.

· 3.

You have learned the basic way in which scientists analyze problems, propose models to explain the systems under consideration, and then experiment to test their models. Suppose you have a sample of a liquid material. You are not sure whether the liquid is a pure compound (for example, water or alcohol) or a solution. How could you apply the scientific method to study the liquid and to determine which type of material the liquid is?

· 4.

Many college students would not choose to take a chemistry course if it were not required for their major. Do you have a better appreciation of why chemistry is a required course for your own particular major or career choice? Discuss.

· 5.

In Chapter 2 of this text, you were introduced to the International System (SI) of measurements. What are the basic units of this system for mass, distance, time, and temperature? What are some of the prefixes used to indicate common multiples and subdivisions of these basic units? Give three examples of the use of such prefixes, and explain why the prefix is appropriate to the quantity or measurement being indicated.

· 6.

Most people think of science as being a specific, exact discipline, with a “correct” answer for every problem. Yet you were introduced to the concept of uncertainty in scientific measurements. What is meant by “uncertainty”? How does uncertainty creep into measurements? How is uncertainty indicated in scientific measurements? Can uncertainty ever be completely eliminated in experiments? Explain.

· 7.

After studying a few chapters of this text, and perhaps having done a few lab experiments and taken a few quizzes in chemistry, you are probably sick of hearing the term significant figures. Most chemistry teachers make a big deal about significant figures. Why is reporting the correct number of significant figures so important in science? Summarize the rules for deciding whether a figure in a calculation is “significant.” Summarize the rules for rounding off numbers. Summarize the rules for doing arithmetic with the correct number of significant figures.

· 8.

This chemistry course may have been the first time you have encountered the method of dimensional analysis in problem solving. Explain the terms conversion factor and equivalence statement. Give an everyday example of how you might use dimensional analysis to solve a simple problem.

· 9.

You have learned about several temperature scales so far in this text. Describe the Fahrenheit, Celsius, and Kelvin temperature scales. How are these scales defined? Why were they defined this way? Which of these temperature scales is the most fundamental? Why?

· 10.

What is matter? What is matter composed of? What are some of the different types of matter? How do these types of matter differ, and how are they the same?

· 11.

It is important to be able to distinguish between the physical and the chemical properties of chemical substances. Choose a chemical substance you are familiar with, then use the Internet or a handbook of chemical information to list three physical properties and three chemical properties of the substance.

· 12.

What is an element, and what is a compound? Give examples of each. What does it mean to say that a compound has a constant composition? Would samples of a particular compound here and in another part of the world have the same composition and properties?

· 13.

What is a mixture? What is a solution? How do mixtures differ from pure substances? What are some of the techniques by which mixtures can be resolved into their components?


Problems with answers below also have full solutions in the Student Solutions Guide.

· 14.

For each of the following, make the indicated conversion.

a. to standard scientific notation

b. to ordinary decimal notation

c. to ordinary decimal notation

d. to standard scientific notation

e. to standard scientific notation


· 15.

For each of the following, make the indicated conversion, showing explicitly the conversion factor(s) you used.

a. kg to grams

b. lbs to grams

c. km to miles

d. ft to miles

e. ft to meters

f. cm to meters

g. L to milliliters

h. qts to liters

· 16.

Without performing the actual calculations, determine to how many significant figures the results of the following calculations should be reported.









· 17.

Chapter 2 introduced the Kelvin and Celsius temperature scales and related them to the Fahrenheit temperature scale commonly used in the United States.

a. How is the size of the temperature unit (degree) related between the Kelvin and Celsius scale?

b. How does the size of the temperature unit (degree) on the Fahrenheit scale compare to the temperature unit on the Celsius scale?

c. What is the normal freezing point of water on each of the three temperature scales?

d. Convert to kelvins and to Fahrenheit degrees.

e. Convert K to Celsius degrees and to Fahrenheit degrees.

f. Convert to kelvins and to Celsius degrees.

· 18.

a. Given that mL of ethyl alcohol weighs g, calculate the density of ethyl alcohol.

b. What volume would kg of ethyl alcohol occupy?

c. What is the mass of L of ethyl alcohol?

d. Pure aluminum metal has a density of . Calculate the volume of g of pure aluminum.

e. What will a rectangular block of pure aluminum having dimensions of weigh?

· 19.

Which of the following represent physical properties or changes, and which represent chemical properties or changes?

a. You curl your hair with a curling iron.

b. You curl your hair by getting a “permanent wave” at the hair salon.

c. Ice on your sidewalk melts when you put salt on it.

d. A glass of water evaporates overnight when it is left on the bedside table.

e. Your steak chars if the skillet is too hot.

f. Alcohol feels cool when it is spilled on the skin.

g. Alcohol ignites when a flame is brought near it.

h. Baking powder causes biscuits to rise.