Standard 1: Objective 1
8th Grade
Unit Summary
Name___________________
Describe Chemical and Physical Properties
Standard I: Students will understand the nature of changes in matter.
Objective 1: Describe the chemical and physical properties of various substances.
Enduring Understanding: Physical properties are characteristics of a substance that can be
observed without changing the identity of the substance. Examples of physical properties are
color, shape, hardness, texture, mass, weight, density and volume. Chemical properties are the
ways in which substances change into new substances. Examples of chemical properties are
flammability and reactivity. The ability to distinguish between the two is the main goal of this
objective.
Essential Questions
1. What is the difference between a chemical property and a physical property?
2. What properties would you use to classify a substance?
3.Where can you find information on the chemical and physical properties of different
substances?
Vocabulary:
Chemical Change: ________________________________________________________________________
Physical Change: _________________________________________________________________________
Reactivity:______________________________________________________________________________
Flammable:_____________________________________________________________________________
Texture:________________________________________________________________________________
Mass:__________________________________________________________________________________
Volume:________________________________________________________________________________
Density:________________________________________________________________________________
Phase Change:___________________________________________________________________________
Melting:_______________________________________________________________________________
Boiling:________________________________________________________________________________
Freezing:_______________________________________________________________________________
All You Need to Read
Standard 1: Objective 1
Chemical and physical changes are the way that matter on Earth changes from one form to
another. To understand chemical and physical change it is important to understand that all substances
have chemical and physical properties that describe the substance.
Chemical properties are ways that the substance reacts and changes into a new substance
when combined with other substances. For example, when an iron nail rusts, it combines with oxygen to
form a new substance, iron oxide or rust. A chemical property of the iron in the nail is that it combines with
oxygen to form rust.
Physical properties are characteristics of the substance that describe how the substance
behaves. For example, physical properties are a substances boiling point, whether it is hard or soft,
flexible or not and its color or hardness.
Substances are often classified on the basis of their chemical and physical properties.
Flammable substances are placed in special containers marked “flammable” to warn people not to light
matches near them. Substances that are poisonous to eat are marked by a skull and crossbones to show
they are dangerous. What groups would you put the following substances in?
Water, gasoline, wood, silver, plastic, milk, glass, steel, copper, paper, air, cloth, diamond, rock
When a new substance is found or created in a lab, scientists do tests to find out the chemical
and physical properties of the substance. They want to know about the substance but they also want to
know what it might be used for. If a new plastic is created in the lab, it might be of value to people if it is
flexible, or not. It might be flame proof or very strong. Any of these properties might make it valuable.
Knowing the chemical and physical properties of a substance will help you know if you should
use it for a particular task. You don’t see many skyscrapers made out of wood. Why? What substance
would you like to know more about?