[WAEL EL CHEHABI July 20, 2012
Reading [20 minutes each passage]
A. Read very carefully through the following passage and then answer the questions that follow it. Write
your answers in the following grid.
1 2 3 4 5 6 7 8 9 10 11 12
"Physical and Chemical Properties and Changes"
→ Sugar, water, and aluminum are different substances. Each substance has specific properties that
do not depend on the quantity of the substance. Properties that can be used to identify or
characterize a substance—and distinguish that substance from other substances—are called
characteristic properties. They are subdivided into two categories: physical properties and chemical
properties.
→The characteristic physical properties of a substance are those thdt identify the substance without
causing a change in the composition of the substance. They do not depend on the quantity of
substance. A Color, odor, density, melting point, boiling point, hardness, metallic luster or shininess,
ductility, malleability, and viscosity are all characteristic physical properties. For exam-ple, aluminum
is a metal that is both ductile and malleable. B Another example of a physical property is water.
Whether a small pan of water is raised to its boiling point or a very large kettle of water is raised
to its boiling point, the temperature at which the water boils is the same value, 100 degrees C or
212 degrees F. C Similarly, the freezing point of water is 0 degrees C or 32 degrees F. These
values are independent of quantity. D
Characteristic properties that relate to changes in the composition of a substance or to how it reacts
with other substances are called chemical properties. The following questions pertain to the chemical
properties of a substance.
1 .Does it burn in air?
2. Does it decompose (break up into smaller substances) when heated?
3. What happens when it is placed in an acid?
4. What other chemicals will it react with, and what substances are obtained from the reaction?
Characteristic physical and chemical properties— also called intensive properties— are used to
identify a substance. In addition to the characteristic physical properties already mentioned, some
intensive physical properties include the tendency to dissolve in water, electrical conductivity, and
density, which is the ratio of mass to volume.
Additional intensive chemical properties include the tendency of a substance to react with another
substance, to tarnish, to corrode, to explode, or to act as a poison or carcinogen (cancer-causing
agent).
Extensive properties of substances are those that depend on the quantity of the sample, including
measurements of mass, volume, and length. Whereas Intensive properties help identify or
characterize a particular kind of matter, extensive properties relate to the amount present.
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 1
,[WAEL EL CHEHABI July 20, 2012
If a lump of candle wax is cut or broken into smaller pieces, or if it is melted (a change of state), the
sample remaining is still candle wax. When cooled, the molten wax returns to a solid, in these
examples, only a physical change has taken place: that is, the composition of the substance was not
affected.
→ When a candle is burned, there are both physical and chemical changes. After the candle is
lighted, the solid wax near the burning wick melts. This is a physical change; the composition of the
wax does not change as it goes from solid to liquid. Some of the wax is drawn into the burning wick
where a chemical change occurs. Here, wax in the candle flame reacts chemically with oxygen in the
air to form carbon dioxide gas and water vapor, in any chemical change, one or more substances
are used up while one or more new substances are formed. The new substances produced have their
own unique physical and chemical properties.
The apparent disappearance of something, like the candle wax, however, is not necessarily a sign
that we are observing a chemical change. For example, when water evaporates from a glass and
disappears, it has changed from a liquid to a gas (called water vapor), but in both forms it is water.
This is a phase change (liquid to gas), which Is a physical change. When attempting to determine
whether a change is physical or chemical, one should ask the critical question: Has the fundamental
composition of the substance changed? In a chemical change (a reaction), it has, but in a physical
change, it has not.
Glossary
ductility: can be drawn into wire malleability: can be shaped viscosity: thick, resistant to flow
1. According to paragraph 1, what do physical properties and chemical properties have in common?
A. They are both used to create most of the substances.
B. They include basic substances like sugar and water.
C. They are classified as characteristic properties of substances.
D. They change in proportion to the amount of the substance.
Paragraph 1 is marked with an arrow [->].
2. The word pertain in the passage is closest in meaning to
A. compare
B. relate
C. explain
D. change
3. The word which in the passage refers to
A. properties
B. tendency
C. density
D. ratio
4. According to the passage, a carcinogen
A. explodes under pressure
B. conducts electricity
C. causes cancer
D. tarnishes in air
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 2
, [WAEL EL CHEHABI July 20, 2012
5. Which of the sentences below best expresses the information in the highlighted statement in the
passage? The other choices change the meaning or leave out important information.
A. Properties that are classified as intensive identify the type of substance and the extent of it
present in the surrounding matter,
B. The quantity of a substance influences its extensive properties, but the characteristics of the
substance define the intensive properties.
C. Where the intensive and extensive properties are found in substances is important in
identifying their characteristics,
D. Both intensive and extensive properties tend to have quantitative rather than qualitative
characteristics present.
6. In paragraph 8, the author contrasts the concepts of physical and chemical changes by
A. listing several types for each concept
B. providing clear definitions for them
C. identifying the common characteristics
D. using a wax candle as an example
Paragraph 8 is marked with an arrow [→].
7. The word unique in the passage is closest in meaning to
A. distinctive
B. idealized
C. primary
D. significant
8. What can be inferred about phase changes?
A. They are always chemical changes.
B. They are sometimes physical changes.
C. They are dependent on extensive properties.
D. They usually produce new substances.
9. The word critical in the passage is closest in meaning to
A. last
B. important
C. difficult
D. simple
10. According to the passage, the classification of characteristic properties as "physical" or
"chemical" is determined by
A. whether there has been a change in the structure of the substance
B. what happens when the quantity of the substance is increased
C. their classification as either extensive or intensive samples
D. the disappearance of a substance from one form to another
11. All of the following are mentioned as characteristic physical properties EXCEPT
A. dissolving in water
B. carrying an electrical charge
C. resisting continuous flow
D. decomposing when heated
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 3
Reading [20 minutes each passage]
A. Read very carefully through the following passage and then answer the questions that follow it. Write
your answers in the following grid.
1 2 3 4 5 6 7 8 9 10 11 12
"Physical and Chemical Properties and Changes"
→ Sugar, water, and aluminum are different substances. Each substance has specific properties that
do not depend on the quantity of the substance. Properties that can be used to identify or
characterize a substance—and distinguish that substance from other substances—are called
characteristic properties. They are subdivided into two categories: physical properties and chemical
properties.
→The characteristic physical properties of a substance are those thdt identify the substance without
causing a change in the composition of the substance. They do not depend on the quantity of
substance. A Color, odor, density, melting point, boiling point, hardness, metallic luster or shininess,
ductility, malleability, and viscosity are all characteristic physical properties. For exam-ple, aluminum
is a metal that is both ductile and malleable. B Another example of a physical property is water.
Whether a small pan of water is raised to its boiling point or a very large kettle of water is raised
to its boiling point, the temperature at which the water boils is the same value, 100 degrees C or
212 degrees F. C Similarly, the freezing point of water is 0 degrees C or 32 degrees F. These
values are independent of quantity. D
Characteristic properties that relate to changes in the composition of a substance or to how it reacts
with other substances are called chemical properties. The following questions pertain to the chemical
properties of a substance.
1 .Does it burn in air?
2. Does it decompose (break up into smaller substances) when heated?
3. What happens when it is placed in an acid?
4. What other chemicals will it react with, and what substances are obtained from the reaction?
Characteristic physical and chemical properties— also called intensive properties— are used to
identify a substance. In addition to the characteristic physical properties already mentioned, some
intensive physical properties include the tendency to dissolve in water, electrical conductivity, and
density, which is the ratio of mass to volume.
Additional intensive chemical properties include the tendency of a substance to react with another
substance, to tarnish, to corrode, to explode, or to act as a poison or carcinogen (cancer-causing
agent).
Extensive properties of substances are those that depend on the quantity of the sample, including
measurements of mass, volume, and length. Whereas Intensive properties help identify or
characterize a particular kind of matter, extensive properties relate to the amount present.
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 1
,[WAEL EL CHEHABI July 20, 2012
If a lump of candle wax is cut or broken into smaller pieces, or if it is melted (a change of state), the
sample remaining is still candle wax. When cooled, the molten wax returns to a solid, in these
examples, only a physical change has taken place: that is, the composition of the substance was not
affected.
→ When a candle is burned, there are both physical and chemical changes. After the candle is
lighted, the solid wax near the burning wick melts. This is a physical change; the composition of the
wax does not change as it goes from solid to liquid. Some of the wax is drawn into the burning wick
where a chemical change occurs. Here, wax in the candle flame reacts chemically with oxygen in the
air to form carbon dioxide gas and water vapor, in any chemical change, one or more substances
are used up while one or more new substances are formed. The new substances produced have their
own unique physical and chemical properties.
The apparent disappearance of something, like the candle wax, however, is not necessarily a sign
that we are observing a chemical change. For example, when water evaporates from a glass and
disappears, it has changed from a liquid to a gas (called water vapor), but in both forms it is water.
This is a phase change (liquid to gas), which Is a physical change. When attempting to determine
whether a change is physical or chemical, one should ask the critical question: Has the fundamental
composition of the substance changed? In a chemical change (a reaction), it has, but in a physical
change, it has not.
Glossary
ductility: can be drawn into wire malleability: can be shaped viscosity: thick, resistant to flow
1. According to paragraph 1, what do physical properties and chemical properties have in common?
A. They are both used to create most of the substances.
B. They include basic substances like sugar and water.
C. They are classified as characteristic properties of substances.
D. They change in proportion to the amount of the substance.
Paragraph 1 is marked with an arrow [->].
2. The word pertain in the passage is closest in meaning to
A. compare
B. relate
C. explain
D. change
3. The word which in the passage refers to
A. properties
B. tendency
C. density
D. ratio
4. According to the passage, a carcinogen
A. explodes under pressure
B. conducts electricity
C. causes cancer
D. tarnishes in air
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 2
, [WAEL EL CHEHABI July 20, 2012
5. Which of the sentences below best expresses the information in the highlighted statement in the
passage? The other choices change the meaning or leave out important information.
A. Properties that are classified as intensive identify the type of substance and the extent of it
present in the surrounding matter,
B. The quantity of a substance influences its extensive properties, but the characteristics of the
substance define the intensive properties.
C. Where the intensive and extensive properties are found in substances is important in
identifying their characteristics,
D. Both intensive and extensive properties tend to have quantitative rather than qualitative
characteristics present.
6. In paragraph 8, the author contrasts the concepts of physical and chemical changes by
A. listing several types for each concept
B. providing clear definitions for them
C. identifying the common characteristics
D. using a wax candle as an example
Paragraph 8 is marked with an arrow [→].
7. The word unique in the passage is closest in meaning to
A. distinctive
B. idealized
C. primary
D. significant
8. What can be inferred about phase changes?
A. They are always chemical changes.
B. They are sometimes physical changes.
C. They are dependent on extensive properties.
D. They usually produce new substances.
9. The word critical in the passage is closest in meaning to
A. last
B. important
C. difficult
D. simple
10. According to the passage, the classification of characteristic properties as "physical" or
"chemical" is determined by
A. whether there has been a change in the structure of the substance
B. what happens when the quantity of the substance is increased
C. their classification as either extensive or intensive samples
D. the disappearance of a substance from one form to another
11. All of the following are mentioned as characteristic physical properties EXCEPT
A. dissolving in water
B. carrying an electrical charge
C. resisting continuous flow
D. decomposing when heated
WAEL EL CHEHABI TOEFL IBT DIAGNOSTIC TEST 3
