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1
Chapter 1 Chemistry in Our Lives
1.2 Some Fundamental Ideas of Chemistry
Copyright © 2005 by Pearson Education, Inc.
Publishing as Benjamin Cummings
2
Matter
Matter • Is what all materials are made of• Has mass• Occupies space• Has characteristics called physical and chemical
properties
3
Physical Properties
Physical properties are:
• Characteristics observed or measured without changing the identify of a substance.
• Shape, physical state, odor, boiling and freezing points, density, and color of that substance.
4
Physical Properties of Copper
Copper has physical properties:
• Reddish-orange
• Very shiny
• Excellent conductor of heat and electricity
• Solid at 25C
• Melting point 1083C
• Boiling point 2567CCopyright © 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings
5
States of Matter
All substances known as matter exist in
one of three forms or states:• Solids
Have definite volumes and shapes• Liquids
Have definite volumes, but take the shapes of containers
• Gases
Have no definite volumes or shapesCopyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
6
Examples of States of Matter
Solids• Rocks, shells, baseballs, tennis racquets, books
Liquids• Lakes, rain, melted gold, mercury in a
thermometer
Gases • Air, helium in a balloon, neon in a neon tube
7
Learning Check
Identify the state of matter for each of the following:
A. Vitamin tablets in a bottle
B. Eye drops
C. Vegetable oil
D. A candle
E. Air in a tire
8
Solution
Identify the state of matter for each of the following:
A. Vitamin tablets in a bottle solid
B. Eye drops liquid
C. Vegetable oil liquid
D. A candle solid
E. Air in a tire gas
9
A physical change occurs in a substance if • There is a change in the state• There is a change in the physical shape
But there is no change in • The identity and composition of the substance
Physical Change
10
Examples of Changes of State
Some changes of state for water: • Solid water (ice) melts to form liquid
water• Liquid water changes to gaseous
water (steam)
Copyright © 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings
11
Examples of Physical Changes
Examples of physical changes: • Paper torn into little pieces
(change of size)• Copper hammered into thin sheets• Water poured into a glass (change
of shape)
Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings
12
Learning Check
Classify each of the following as a
1) change of state 2) change of shape
A. Chopping a log into kindling
B. Water boiling in a pot
C. Ice cream melting
D. Ice forming in a freezer
E. Cutting dough into strips
13
Solution
Classify each of the following changes as a
1) change of state 2) change of shape
A. Chopping a log into kindling (2)
B. Water boiling in a pot (1)
C. Ice cream melting (1)
D. Ice forming in a freezer (1)
E. Cutting dough into strips (2)
14
Chemical Properties
Chemical properties describe the ability of a substance• To interact with other substances• To change into a new substance
Example:
Iron has the ability to form rust
when exposed to oxygen.
Copyright © 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings
15
Learning Check
Classify each of the following properties as physical
or chemical:
A. Ice melts in the sun
B. Copper is a shiny metal
C. Paper can burn
D. A silver knife can tarnish
E. A magnet removes particles of iron from a mixture
of sugar and iron
16
Solution
Classify each of the following properties as physical
or chemical:
A. Ice melts in the sun physical
B. Copper is a shiny metal physical
C. Paper can burn chemical
D. A silver knife can tarnish chemical
E. A magnet removes particles physical
of iron from a mixture
of sugar and iron
17
Chemical Change
In a chemical change or chemical
reaction, a new substance forms
that has• A new composition• New chemical properties• New physical properties
Copyright © 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings
18
Some Chemical Changes
Silver tarnishes
Shiny metal reacts to form black, grainy coating
Wood burns
A piece of wood burns with a bright flame to form ash, carbon dioxide, water vapor, and heat.
Iron rusts
A shiny nail combines with oxygen to form orange-red rust.
19
Classify each of the following changes as physical or
chemical:
A. Burning a candle
B. Ice melting on the street
C. Toasting a marshmallow
D. Cutting a pizza
E. Iron rusting on an old car
Learning Check
20
Classify each of the following changes as physical or
chemical:
A. Burning a candle chemical
B. Ice melting on the street physical
C. Toasting a marshmallow chemical
D. Cutting a pizza physical
E. Iron rusting on an old car chemical
Solution