properties and changes in matter extensive properties depend on the amount of matter that is...
TRANSCRIPT
Properties and Changes in Matter
• Extensive properties depend on the amount of matter that is present.
• volume
• mass
• the amount of energy in a substance.
Section 2 Matter and Its PropertiesChapter 1
Properties and Changes in Matter
• Intensive properties do not depend on the amount of matter present.
• melting point
• boiling point
• density
• ability to conduct electricity
• ability to transfer energy as heat
Section 2 Matter and Its PropertiesChapter 1
Click below to watch the Visual Concept.
Visual Concept
Chapter 1
Comparing Extensive and Intensive Properties
Section 2 Matter and Its Properties
Physical Properties and Physical Changes
• A physical property is a characteristic that can be observed or measured without changing the identity of the substance.
• melting point and boiling point
• A physical change is a change in a substance that does not involve a change in the identity of the substance.
• grinding, cutting, melting, and boiling
Section 2 Matter and Its PropertiesChapter 1
Chemical Properties and Chemical Changes
• A chemical property relates to a substance’s ability
to undergo changes that transform it into different
substances
• A change in which one or more substances are
converted into different substances is called a
chemical change or chemical reaction.
Section 2 Matter and Its PropertiesChapter 1
Chemical Properties and Chemical Changes, continued
• The products are the substances that are formed by
the chemical change.
Section 2 Matter and Its PropertiesChapter 1
reactants product
• The reactants are the substances that react in a
chemical change.
Carbon plus oxygen yields (or forms) carbon dioxide.
carbon + oxygen carbon dioxide
Evidence of a Chemical Change
Section 2 Matter and Its PropertiesChapter 1
Section 3 ElementsChapter 1
Regions of the Periodic Table
Introduction to the Periodic Table
• The vertical columns of the periodic table are called
groups, or families. • Each group contains elements with similar
chemical properties.
• The horizontal rows of elements in the periodic table
are called periods. • Physical and chemical properties change
somewhat regularly across a period.
Section 3 ElementsChapter 1
Types of Elements Metals
• A metal is an element that is a good electrical conductor and a good heat conductor.
• Properties of metals
• most are solids at room temperature
• malleable - they can be hammered or rolled into thin sheets
• ductile - they can be drawn into a fine wire
• conduct electricity and heat well
Section 3 ElementsChapter 1
Types of Elements
• Gold, copper, and aluminum are metals
Section 3 ElementsChapter 1
Types of Elements
Nonmetals • A nonmetal is an element that is a poor conductor of
heat and electricity.
• Properties of nonmetals
• many are gases
• solids are brittle
• poor conductors of heat and electricity
Section 3 ElementsChapter 1
Types of Elements
• Various nonmetal elements (a) carbon, (b) sulfur, (c) phosphorus, and (d) iodine
Section 3 ElementsChapter 1
Types of Elements
Metalloids • A metalloid is an element that has some
characteristics of metals and some characteristics of
nonmetals.
• Properties of metalloids• all metalloids are solids at room temperature• semiconductors of electricity
Section 3 ElementsChapter 1
Types of Elements
Noble Gases
Section 3 ElementsChapter 1
• elements in Group 18 of the periodic table• generally unreactive• gases at room temperature
Short Answer
11. In trying to identify a sample of a pure substance, we observe the following properties. Tell whether each one is a chemical property or a physical property.
A. Its mass is 124.3 g.
B. It is a shiny solid at room temperature.
C. It is easily etched by nitric acid.
D. It melts when heated to 670°C.
E. It is 31.7 centimeters long.
F. It is a good heat conductor.
G. It burns in air.
H. It is a good conductor of electrical energy.
Standardized Test Preparation Chapter 1
11. In trying to identify a sample of a pure substance, we observe the following properties. Tell whether each one is a chemical property or a physical property.
A. Its mass is 124.3 g. physical property
B. It is a shiny solid at room temperature. physical
property
C. It is easily etched by nitric acid. chemical
property
D. It melts when heated to 670°C. physical
property
E. It is 31.7 centimeters long. physical
property
F. It is a good heat conductor. physical property
G. It burns in air. chemical
property
H. It is a good conductor of electrical energy. physical
property
Short Answer
Standardized Test Preparation Chapter 1
Extended Response
Standardized Test Preparation Chapter 1
13. Describe general properties of metals, nonmetals, and metalloids.
13. Describe general properties of metals, nonmetals, and metalloids.
Answer: metals: shiny; good conductors of heat; good conductors of electricity; malleable or ductile; most are solids at room temperature
nonmetals: poor conductors of heat; poor conductors of electricity; many are gases at room temperature; those that are solids are brittle rather than malleable or ductile
metalloids: properties intermediate between those of metals and nonmetals; less malleable than metals but not as brittle as solid nonmetals; most are semiconductors of electricity
Standardized Test Preparation Chapter 1
Extended Response