Changes in Matter

Chapter 2 Unit ELesson 1 and 2

What Are Physical Changes?

Physical change is a change that does not form any new matter.

Paper that is folded and cut in pieces.

Ways to cause a physical change

Cutting and folding things.Changing things from solid to liquid or

from gas to liquid to solidWriting on somethingMixing things togetherSeparating mixtures

MixturesA mixture is a substance that contains two

or more different types of matter.Some mixtures can be separated by hand.

PerspirationPerspiration is a mixture of water and solid

waste substances, such as salt, produced by the body. When the body becomes over-heated, sweat glands release perspiration through pores in the skin. The liquid portion evaporates quickly as it moves across the skin’s surface.

EvaporationIn evaporation a liquid part of a mixture

turns into a gas. This leaves the other parts behind.

CondensationIn condensation a gas in a mixture turns

into a liquid. The liquid can be separated from the rest of the mixture.

SolutionsIn a solution the particles of the different

kinds of matter mix together evenly.

Tea

s

What are Chemical Changes?

Changes that form different kinds of matter. Cooking food makes new kinds of matter.

Some chemical change

People burn things every day. Many people burn oil or gas to heat their homes. When things burn, different kinds of matter form. When wood burns, it combines with oxygen in the air. The matter that forms includes smoke and ash. Another kind of matter forms that you can’t see. It is a gas that mixes with the air.

RustingRust forms when air and water mix with

the iron in metal. The rust is a different kind of matter. It is flaky and soft. When metal gets rusty, it loses some of its strength. Rusting is a chemical change.

Rusty nailnail

Rust makes metal weak.