Supplemental
Worksheets
Name
Date
Class
Quick Vocabulary
Lesson 1
Lesson 2
atom small particle that is the
atomic number the number of
building block of matter
chemical change a change in matter
in which the substances that make
up the matter change into other
substances with different chemical
and physical properties
compound substance made of
two or more elements that are
chemically joined in a specific
combination
element substance made of only one
kind of atom
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
heterogeneous mixture a mixture
protons in the nucleus of an atom
of an element
charge electrical property of some
objects that determines whether
the object is positive, negative, or
neutral
electron negatively charged particle
that occupies the space in an atom
outside the nucleus
electron cloud region surrounding
an atom’s nucleus where one or
more electrons are most likely to
be found
in which the substances are not
evenly mixed
ion atom that has a charge because
homogeneous mixture a mixture in
isotope one of two or more atoms
which two or more substances are
evenly mixed, but not bonded
together
individual single; separate
matter anything that has mass and
takes up space
mixture matter that can vary in
composition
molecule two or more atoms that
are held together by chemical
bonds and act as a unit
it has gained or lost electrons
of an element having the same
number of protons, but a different
number of neutrons
neutron uncharged particle in the
nucleus of an atom
nucleus region at the center of an
atom that contains most of the
mass of the atom
proton positively charged particle in
the nucleus of an atom
substance matter with a composition
that is always the same
Matter and Atoms
3
Name
Date
Class
Lesson Outline
LESSON 1
Substances and Mixtures
A. What is matter?
1. Anything that has mass and takes up space is considered to
be
.
2. Types of
, including heat, sound, and electricity, and
such as magnetism and gravity are not matter.
B. What is matter made of?
1. The building blocks of matter are small particles called
.
2. The different ways that atoms combine with each other help us identify different
types of
.
C. Classifying Matter
1. Scientists classify all matter into two main groups:
and
.
2. The difference between the two main kinds of matter is
their
.
1. Matter with a composition that is always the same is
a(n)
.
2. A substance made up on only one kind of atom, such as gold is
a(n)
.
a. Some elements are formed of
, which are units
formed of two or more atoms that are held together by chemical bonds.
b. There are about 115 elements, each of which has its own
chemical
.
3. A(n)
is a substance made up of two or more elements
that are chemically joined in a specific combination; most matter is formed
of
.
E. What is a mixture?
1. Matter that can vary in its composition is a(n)
2. The substances that make up
10
.
are not bonded together.
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
D. What is a substance?
Name
Date
Class
Lesson Outline continued
F. Types of Mixtures
1. Mixtures differ in how
the substances that form them
are mixed.
2. A mixture, such as trail mix, in which the substances are not evenly mixed is
a(n)
mixture.
3. A mixture in which two or more substances are evenly mixed, but not bonded
together is a(n)
mixture, also called
a(n)
.
4. All three states of matter can be a(n)
or a solvent in
a solution.
G. Compounds v. Mixtures
1. The parts of any kind of
, including trail mix, soda,
and air, keep their properties.
2. The atoms that make up a(n)
are bonded together, so
its composition is always the same.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
3. The substances that make up a(n)
are not bonded
together, so adding more of one substance in a solution will not change the
composition of the solution.
4. You can separate the parts of any mixture by using
processes.
a. A(n)
, a strainer, or a ladle can be used to separate the
parts of a(n)
mixture.
b. The best methods for separating a(n)
solution—is to use
mixture—a
or evaporation.
H. Visualizing Classification of Matter
1. Matter can be classified as a(n)
a(n)
or
.
2. A substance can be classified as a(n)
a(n)
or
.
3. A mixture can be classified as
or
.
4. All the matter in every category is made up of
Matter and Atoms
.
11
Name
Date
Class
Content Practice A
LESSON 1
Substances and Mixtures
Directions: Use the clues to complete the crossword puzzle.
1
4
2
5
3
6
7
8
Clues
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Across
1. a mixture in which two or more
substances are evenly mixed but not
bonded together
6. a mixture in which the substances are
not evenly mixed
7. two or more atoms that are held
together by chemical bonds and act
as a unit
8. matter with a composition that is
Down
2. anything that has mass and takes
up space
3. substance made of only one kind of
atom
4. a small particle that is the building
block of matter
5. substance made of two or more
elements that are chemically joined
in a specific combination
always the same
Matter and Atoms
13
Name
Date
Class
Content Practice B
LESSON 1
Substances and Mixtures
Directions: On the line before each statement, write T if the statement is true or F if the statement is false. If the
statement is false, change the underlined word(s) to make it true. Write your changes on the lines provided.
1. Gravity is matter because it does not have mass and volume.
2. Each type of atom has a different number of smaller particles.
3. The composition of a substance is always the same.
4. The substances in a mixture are bonded together.
5. All atoms of an element are alike.
7. Elements can be classified as metals, nonmetals, and metalloids.
8. Compounds are made of atoms of the same element bonded together.
9. Soda is an example of a heterogeneous mixture, or a mixture in which two or
more substances are evenly mixed but not bonded together.
14
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
6. The atoms in a molecule are held together by chemical bonds.
Name
Date
Class
Key Concept Builder
LESSON 1
Substances and Mixtures
Key Concept What is the relationship among atoms, elements, and compounds?
Directions: Answer each question or respond to each statement in the space provided.
1. What is an atom?
2. What happens when atoms
combine?
3. What is an element?
4. Name three elements.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
5. What is the relationship among
atoms, elements, and molecules?
6. What is a compound?
7. Name three compounds.
8. What information about a
compound is found in its
chemical formula?
9. How are atoms related to
elements and compounds?
16
Matter and Atoms
Name
Date
Key Concept Builder
Class
LESSON 1
Substances and Mixtures
Key Concept How are some mixtures different from solutions?
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Directions: On the line before each item, write HE if the item represents a heterogeneous mixture or HO if the
item represents a homogeneous mixture.
1.
granite
2.
smoke
3.
soda
4.
brass
5.
trail mix
6.
air
7.
tap water
Directions: Answer each question on the lines provided.
8. What is the difference between a heterogeneous mixture and a homogeneous mixture?
9. Which mixtures listed in the activity above are solutions? Explain your answer.
Matter and Atoms
17
Name
Date
Class
Key Concept Builder
LESSON 1
Substances and Mixtures
Key Concept How do mixtures and compounds differ?
Directions: Complete the chart by writing the correct term from the word bank on the lines provided. Some terms
may be used more than once or not at all.
atoms
compounds
elements
heterogeneous mixture
homogeneous mixture
mass
matter
mixtures
substances
Matter
• anything that has (1.)
and takes up space
• most made of (2.)
• two classifications: (3.)
and (4.)
(5.)
• made up of one or more types of atoms in the same combinations
• two types: (6.)
and (7.)
(9.)
• made of only one type of atom
• organized on the periodic table
• made of two or more types of atoms bonded
together
• properties are different from the elements
that make it up
• have a chemical symbol
• have chemical formulas
(10.)
• made of two or more (11.)
that are not bonded together
• Combinations of subtances can vary.
• two types: (12.)
(14.)
and (13.)
(15.)
• two or more substances unevenly mixed
• two or more substances evenly mixed
• different substances visible by unaided eye
or microscope
• Different substances cannot be seen by a
microscope.
18
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
(8.)
Name
Date
Class
Key Concept Builder
LESSON 1
Substances and Mixtures
Key Concept How do mixtures and compounds differ?
Directions: Put a check mark on the line before each property that is typical of a compound.
1. made of only one kind of atom
2. made of unbonded substances
3. is a substance
4. made of elements that are bonded together
5. represented by a chemical formula
6. Identity is not changed by changing the amount of its substances.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
7. is the smallest part of an element
8. is often made of molecules
Directions: Respond to each statement on the lines provided.
9. Compare the composition of a mixture and a compound.
10. Compare what happens when you change the composition of a mixture and a compound.
Matter and Atoms
19
Name
Date
Lesson Quiz A
Class
LESSON 1
Substances and Mixtures
Multiple Choice
Directions: On the line before each question or statement, write the letter of the correct answer.
1. Some substances are chemically combined in specific combinations. These are
A. compounds.
B. homogeneous mixtures.
C. heterogeneous mixtures.
2. Which item is a form of matter?
A. air
B. sound
C. gravity
3. Which item is a substance?
A. trail mix
B. table salt
C. breakfast cereal
True or False
Directions: On the line before each statement, write T if the statement is true or F if the statement is false. If the
statement is false, change the underlined word to make it true. Write your changes on the lines provided.
5. Matter with a composition that is always the same is called a(n) substance.
6. A(n) atom is a small particle that is the building block of matter.
7. A molecule is made up of two or more compounds.
8. A(n) mixture is matter that can vary in composition.
22
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
4. A(n) compound is a substance made up of one kind of atom.
Name
Date
Class
Lesson Quiz B
LESSON 1
Substances and Mixtures
Multiple Choice
Directions: On the line before each question, write the letter of the correct answer.
1. Which statement describes a compound?
A. It contains a solute.
B. Its composition can vary.
C. Its combination of atoms never changes.
D. Its components keep separate properties.
2. Which item is NOT a type of matter?
A. force
B. mixture
C. element
D. compound
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
3. Which combination can be used to classify all the matter on Earth?
A. forces and energy
B. atoms and elements
C. solvents and solutes
D. substances and mixtures
Completion
Directions: On each line, write the term from the word bank that correctly completes each sentence. Not all
terms are used.
atom
compound
element
mixture
molecule
substance
4. A(n)
is a substance that is made up of one kind of atom.
5. Matter that has a composition that is always the same is
a(n)
.
6. A(n)
is the basic building block of matter.
7. A(n)
is composed of two or more atoms held together by
chemical bonds.
8. Matter that can vary in composition is a(n)
Matter and Atoms
.
23
Name
Date
Class
Lesson Outline
LESSON 2
The Structure of Atoms
A. The Parts of an Atom
1. Every kind of element is made up of its own kind of
.
2. Atoms are composed of several basic types of very small
; the
of each of these
particles gives the different kinds of atoms their unique identity.
3. The region at the center of an atom that contains most of the mass of the atom is
called the
.
a. A positively charged particle in the nucleus of an atom is called
a(n)
.
b. An uncharged particle in the nucleus of an atom is called
a(n)
.
4. A negatively charged particle that occupies the space in an atom outside the
nucleus is called a(n)
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
a.
.
are much smaller in size than
and neutrons, and they move very quickly.
b. The region surrounding an atom’s nucleus where one or more electrons are most
likely to be found is called a(n)
.
c. An electron cloud is mostly made up of
not a cloud of
d. The electrons closest to the
electrons farthest from the
space; it is
.
have the least energy; the
have the most energy.
B. The Size of Atoms
1. All the substances around you, including your body and the air you breathe are
made up of millions and millions of
.
2. If you could enlarge an atom to be 1 million times larger than its natural size, it
would be the size of a(n)
same degree would be the size of
Matter and Atoms
; this object enlarged to the
.
27
Name
Date
Class
Lesson Outline continued
C. Differences in Atoms
1. Every atom has a(n)
charged nucleus surrounded by
charged electron cloud; however, atoms can have
a(n)
different numbers of
, neutrons, and electrons.
2. The number of protons in the nucleus of an atom of an element is called
the
.
a. Each
has a different atomic number.
b. The number of
in the nucleus of the atom
determines the identity of the atom.
3. One of two or more atoms of an element having the same number of protons but
a different number of neutrons is called a(n)
.
4. A neutral atom has the same number of
as
in its nucleus
in its electron cloud.
a. A neutral atom can gain one or more
, giving the
charge; a neutral atom can lose one or
, giving the atom a(n)
atom a(n)
more
charge.
a(n)
.
c. Ions have same number of
and are the same element
they were before gaining or losing electrons.
D. Atoms and Matter
1. All atoms of the same element have the same number
of
.
2. For each element, the number of
and the number of
can vary.
3. The properties of an element and the ways its
combine
are determined mainly by the number and the arrangement of the
in its atoms.
28
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
b. An atom that has a charge because it has gained or lost electrons is called
Name
Date
Class
Content Practice A
LESSON 2
The Structure of Atoms
Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is
used only once.
1. positively charged particle in the nucleus of
an atom
2. region surrounding an atom’s nucleus where one
or more electrons are often found
3. negatively charged particle that occupies the
space in an atom outside the nucleus
A. atomic number
B. electron
C. electron cloud
D. ion
E. isotope
F. nucleus
4. one or more atoms of an element having the
same number of protons but a different number
of neutrons
G. neutron
H. proton
5. region at the center of an atom that contains
most of the mass of an atom
6. an atom that has a charge because it has gained
or lost electrons
7. the number of protons in the nucleus of an atom
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
of an element
8. uncharged particle in the nucleus of an atom
30
Matter and Atoms
Name
Date
Content Practice B
Class
LESSON 2
The Structure of Atoms
Directions: Circle the term in parentheses that correctly completes each sentence.
1. The nucleus of an atom contains (protons/electrons) and neutrons.
2. The nucleus has a (positive charge/negative charge) and the (least mass/most mass)
of the atom.
3. An electron is a (positively charged/negatively charged) particle located outside the nucleus.
4. The modern model of an atom is called the (electron-cloud/nucleus-orbit) model.
5. Electrons that are close to the nucleus have (more energy/less energy) than electrons
that are farther from the nucleus.
6. The atomic number is the number of (protons/neutrons) in the nucleus of an atom
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
of an element.
7. Isotopes have the same number of protons but different numbers of (electrons/neutrons).
8. An ion has a charge because it has gained or lost (protons/electrons).
9. A (positive/negative) ion has more protons than electrons.
10. Adding a(n) (proton/electron) to a neutral atom produces a new element.
Matter and Atoms
31
Name
Date
Language Arts Support
Class
LESSON 2
Word-Meaning Activity: Using Antonyms
Words with opposite meanings are called antonyms. For example, the words hot and cold
are antonyms.
Directions: On the line before each word in the numbered column, write the letter of the correct antonym.
1. part
A. negative
2. substance
B. compound
3. positive
C. multiple
4. proton
D. solute
E. mixture
5. heterogeneous
F. homogeneous
6. individual
G. whole
7. solvent
H. electron
8. element
I. detach
9. bond
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
32
Matter and Atoms
Name
Date
Class
Language Arts Support
LESSON 2
Word-Meaning Activity: Using Scientific Words
Directions: Study the terms and definitions below. On the line before each definition, write the letter of the term
that matches it correctly. Not all terms are used. NOTE: You may need to change a term to its plural form.
A. atom n. a small particle that is the building block of matter
B. electron n. negatively charged component of an atom
C. proton n. positively charged component of an atom
D. neutron n. uncharged component of an atom
E. ion n. an atom with a charge
F. nucleus n. the center part of an atom
G. electron cloud n. the outer part of an atom
1. Isotopes have the same number of protons as other atoms of the same element,
but different numbers of
.
2. Protons and neutrons are found in an atom’s
.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
3. Electrons are found in an atom’s
, which is mostly
empty space.
4. An element is made up of just one type of
5. Na+ is an example of a(n)
.
.
6. The negative charges of an atom’s electrons are balanced by the atom’s
.
Matter and Atoms
33
Name
Date
Class
Math Skills
LESSON 2
Use Scientific Notation
Measurements of atoms, such as amounts, distances, and weights, are often very large or
very small when compared to measurements of things you can see or touch. Scientific
notation represents numbers as a power of 10. This makes very large or small numbers
easier to use and understand.
Approximately 7,500,000,000,000 carbon atoms fit across the period that you make with
your pencil. Express this number in scientific notation.
Step 1 Rewrite the number with a decimal after the first nonzero digit.
7.500000000000
Find the number of places and the direction you moved the decimal. If a number
does not show a decimal, the decimal is at the right end of the number.
You moved the decimal 12 places to the left.
Step 3
Drop the zeros, and write the number of places you moved the decimal as a power
of 10. If you moved the decimal to the right, the power is negative. If you moved
the decimal to the left, the power is positive.
7.5 × 1012
Step 4
Reverse the process to change scientific notation back to a whole number. A
positive power of 10 moves the decimal to the right. A negative power of 10 moves
the decimal to the left.
Practice
1. A sample of gold contains
3,800,000,000,000,000,000 atoms.
Express this number in scientific
notation.
4. A sample of silicon contains
5.23 × 1011 atoms. Write this amount
as a whole number.
2. A sample of silver contains
400,000,000,000,000 atoms. Express
this number in scientific notation.
5. The mass of a proton is about
1.67 × 10-27 kg. Write this mass as a
whole number.
3. A sample of carbon has a mass of
0.000000000000000000034 kg. Express
this mass in scientific notation.
34
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Step 2
Name
Date
Key Concept Builder
Class
LESSON 2
The Structure of Atoms
Key Concept Where are protons, neutrons, and electrons located in an atom?
Directions: Label this diagram by writing the correct term on each line.
1.
2.
3.
Directions: Answer each question or respond to each statement on the lines provided.
4. Which particle in an atom has a positive charge?
5. Which particle in an atom has no charge?
7. Where is most of the mass of an atom found?
8. Describe the structure of the atom in the diagram above. How many of each type of
particle does the atom have?
36
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
6. Which particle in an atom has a negative charge?
Name
Date
Class
Key Concept Builder
LESSON 2
The Structure of Atoms
Key Concept How is the atomic number related to the number of protons in an atom?
Directions: On each line, write the term or phrase that correctly completes each sentence.
1. The
is the number of protons in the nucleus of an atom of
an element.
2. You can identify an element if you know its atomic number or
3. In the periodic table, the atomic number of an element is the
above its symbol.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Directions: Complete the chart with the correct numbers on the lines provided.
Element
Atomic Number
magnesium
12
carbon
oxygen
Matter and Atoms
Number of Protons
4.
Number of Electrons
5.
6
6.
8
7.
6
8.
37
Name
Date
Class
Key Concept Builder
LESSON 2
The Structure of Atoms
Key Concept What effect does changing the number of particles in an atom have on the
atom’s identity?
Directions: Complete the chart with the correct terms or numbers from the word bank on the lines provided.
Some terms or numbers may be used more than once or not at all.
isotope
5
negative ion
6
7
new element
8
9
positive ion
10
11
12
Possible Changes in Atoms
Neutron Atom
carbon
6 protons
6 neutrons
6 electrons
carbon
6 protons
6 neutrons
6 electrons
carbon
6 protons
6 neutrons
6 electrons
38
add one proton
add one neutron
add one electron
lose one electron
Results
1.
2.
protons
3.
neutrons
4.
electrons
5.
6.
protons
7.
neutrons
8.
electrons
9.
10.
protons
11.
neutrons
12.
electrons
13.
14.
protons
15.
neutrons
16.
electrons
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
carbon
6 protons
6 neutrons
6 electrons
Change
Name
Date
Class
Key Concept Builder
LESSON 2
The Structure of Atoms
Key Concept What effect does changing the number of particles in an atom have on the
atom’s identity?
Directions: On the line before each statement, write the letter of the correct answer.
1. Changing the number of protons in an atom makes
A. an ion.
B. an isotope.
C. a new element.
2. If an atom has 6 protons, 6 neutrons, and 6 electrons, its isotope would have a
different number of
A. protons.
B. neutrons.
C. electrons.
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
3. An atom with the same number of protons and electrons has a
A. neutral charge.
B. positive charge.
C. negative charge.
4. An atom that has a charge because it has gained or lost electrons is
A. an ion.
B. an isotope.
C. a new element.
5. A positive ion has more
A. protons than electrons.
B. electrons than protons.
C. neutrons than protons.
6. A negative ion has more
A. protons than electrons.
B. electrons than protons.
C. neutrons than protons.
7. The number of electrons in atoms can change when elements combine to form
A. isotopes.
B. molecules.
C. compounds.
Matter and Atoms
39
Name
Date
Class
Lesson Quiz A
LESSON 2
The Structure of Atoms
Matching
Directions: On the line before each definition, write the letter of the term that matches it correctly. Each term is
used only once.
Matching Set 1
1. positively charged particle in the nucleus of
an atom
2. negatively charged particle that occupies the
A. electron
B. neutron
C. proton
space in an atom outside the nucleus
3. uncharged particle in the nucleus of an atom
Matching Set 2
4. one of two or more atoms of an element that
have different numbers of neutrons
5. region at the center of an atom
D. nucleus
E. ion
F. isotope
6. an atom that has a positive or negative charge
Multiple Choice
7. An element’s atomic number tells how many
are in the nucleus of an
atom of that element.
A. protons
B. neutrons
C. electrons
8. Where is an atom’s electron cloud located?
A. inside the nucleus
B. outside of the atom
C. surrounding the nucleus
42
Matter and Atoms
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Directions: On the line before each question or statement, write the letter of the correct answer.
Name
Date
Class
Lesson Quiz B
LESSON 2
The Structure of Atoms
Matching
Directions: On the line before each definition, write the letter of the term that matches it correctly. Not all terms
are used.
1. The part of an atom that contains most of
its mass
2. particle in the nucleus of an atom that has a
positive charge
A. electron
B. nucleus
C. neutron
D. electron cloud
3. particle of an atom that has a negative charge
E. ion
4. an atom that has a positive or negative charge
F. isotope
5. uncharged particle in the nucleus of an atom
G. proton
6. one of two or more atoms of an element that
have different numbers of neutrons
Multiple Choice
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Directions: On the line before each statement, write the letter of the correct answer.
7. An element’s atomic number tells the number of
A. isotopes it forms.
B. protons in the nucleus.
C. particles in the nucleus.
D. electrons it gains to form an ion.
8. In an atom, electrons
A. are paired with protons.
B. are found within the nucleus.
C. stay in a region called the electron cloud.
D. orbit the nucleus like planets around the Sun.
Matter and Atoms
43
Lesson Outline for Teaching
Lesson 1: Substances and Mixtures
A. What is matter?
1. Anything that has mass and takes up space is considered to be matter.
and gravity are not matter.
2. Types of energy, including heat, sound, and electricity, and forces such as magnetism
1. The building blocks of matter are small particles called atoms.
B. What is matter made of?
types of matter.
2. The different ways that atoms combine with each other help us identify different
C. Classifying Matter
1. Scientists classify all matter into two main groups: substances and mixtures.
2. The difference between the two main kinds of matter is their composition.
D. What is a substance?
1. Matter with a composition that is always the same is a(n) substance.
2. A substance made up on only one kind of atom, such as gold is a(n) element.
atoms that are held together by chemical bonds.
a. Some elements are formed of molecules, which are units formed of two or more
b. There are about 115 elements, each of which has its own chemical symbol.
joined in a specific combination; most matter is formed of compounds.
3. A(n) compound is a substance made up of two or more elements that are chemically
1. Matter that can vary in its composition is a(n) mixture.
E. What is a mixture?
2. The substances that make up mixtures are not bonded together.
1. Mixtures differ in how evenly the substances that form them are mixed.
F. Types of Mixtures
heterogeneous mixture.
2. A mixture, such as trail mix, in which the substances are not evenly mixed is a(n)
together is a(n) homogeneous mixture, also called a(n) solution.
3. A mixture in which two or more substances are evenly mixed, but not bonded
4. All three states of matter can be a(n) solute or a solvent in a solution.
properties.
Matter and Atoms
1. The parts of any kind of mixture, including trail mix, soda, and air, keep their
G. Compounds v. Mixtures
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Lesson Outline continued
always the same.
2. The atoms that make up a(n) compound are bonded together, so its composition is
of one substance in a solution will not change the composition of the solution.
3. The substances that make up a(n) solution are not bonded together, so adding more
4. You can separate the parts of any mixture by using physical processes.
heterogeneous mixture.
a. A(n) magnet, a strainer, or a ladle can be used to separate the parts of a(n)
use boiling or evaporation.
b. The best methods for separating a(n) homogeneous mixture—a solution—is to
1. Matter can be classified as a(n) substance or a(n) mixture.
H. Visualizing Classification of Matter
2. A substance can be classified as a(n) element or a(n) compound.
3. A mixture can be classified as homogeneous or heterogeneous.
4. All the matter in every category is made up of atoms.
Discussion Question
Name three different solutions. For each solution, identify the solvent and the solute and
explain your answer.
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Students might pick any of the following common solutions, which are discussed in the lesson:
soda, with a solvent of water and solutes of carbon dioxide gas and sugar; saltwater, with a
solvent of water and a solute of salt; brass, with a solvent of copper and a solute of zinc;
ammonia cleaner, with a solvent of water and a solute of ammonia gas. With any of the
examples, students should recognize that the solvent is present in the solution in the largest
amount and the solute is present in the smallest amount.
Matter and Atoms
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Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
Lesson Outline for Teaching
Lesson 2: The Structure of Atoms
1. Every kind of element is made up of its own kind of atoms.
A. The Parts of an Atom
2. Atoms are composed of several basic types of very small particles; the number of
each of these particles gives the different kinds of atoms their unique identity.
3. The region at the center of an atom that contains most of the mass of the atom is
called the nucleus.
a. A positively charged particle in the nucleus of an atom is called a(n) proton.
b. An uncharged particle in the nucleus of an atom is called a(n) neutron.
Lesson Outline continued
electron cloud.
4. A neutral atom has the same number of protons in its nucleus as electrons in its
a. A neutral atom can gain one or more electrons, giving the atom a(n) negative
charge; a neutral atom can lose one or more electrons, giving the atom a(n)
positive charge.
b. An atom that has a charge because it has gained or lost electrons is called a(n) ion.
gaining or losing electrons.
c. Ions have same number of protons and are the same element they were before
Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.
2. For each element, the number of electrons and the number of neutrons can vary.
1. All atoms of the same element have the same number of protons.
D. Atoms and Matter
nucleus is called a(n) electron.
4. A negatively charged particle that occupies the space in an atom outside the
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Ions that have opposite charges are attracted to one another, which is why these ions can
bond with one another. Ions that have the same charge are not able to bond and actually
repel each other.
Why do you think certain ions are able to bond with one another? Why are some ions not
able to bond with one another, and what happens if these ions are near each other?
Discussion Question
mainly by the number and the arrangement of the particles in its atoms.
3. The properties of an element and the ways its atoms combine are determined
very quickly.
a. Electrons are much smaller in size than protons and neutrons, and they move
likely to be found, is called a(n) electron cloud.
b. The region surrounding an atom’s nucleus, where one or more electrons are most
c. An electron cloud is mostly made up of empty space; it is not a cloud of charge.
d. The electrons closest to the nucleus have the least energy; the electrons farthest
from the nucleus have the most energy.
B. The Size of Atoms
made up of millions and millions of atoms.
1. All the substances around you, including your body and the air you breathe are
2. If you could enlarge an atom to be 1 million times larger than its natural size, it
would be the size of a(n) orange; this object enlarged to the same degree would be
the size of Earth.
C. Differences in Atoms
1. Every atom has a(n) positively charged nucleus surrounded by a(n) negatively
charged electron cloud; however, atoms can have different numbers of protons,
neutrons, and electrons.
atomic number.
2. The number of protons in the nucleus of an atom of an element is called the
a. Each element has a different atomic number.
the atom.
b. The number of protons in the nucleus of the atom determines the identity of
a different number of neutrons is called a(n) isotope.
Matter and Atoms
3. One of two or more atoms of an element having the same number of protons but
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Copyright © Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.