Chapter 2 – Properties of Matter

Section 1 – Classifying Matter

Key Objectives

Why are elements and compounds classified as pure substances?

How do mixtures differ from pure substances?

What is the main difference among solutions, suspensions, and colloids?

C la ss ifying M a tte r

H e te ro ge n eo us H o m o ge n eo us

M ix tu re

E le m e nt C o m p o un ds

S u bs ta nces

M a tte r

Matter Chart

Substances

Substances Matter that always has the same composition

Table Salt Table Sugar

Classified into two categories Elements Compounds

Elements

A substance that cannot be broken down into simpler substances Chopping copper into extremely small

particles Atoms – Smallest particle of an element

No two elements have the same type of atom

Element Examples

Oxygen Aluminum Iron Gold

Compounds

Substance composed of 2 or more elements and can be broken down into those elements Water

Oxygen and Hydrogen Sodium Chloride (Salt)

Sodium and Chlorine

Mixtures

Unlike a substance, a mixture does NOT have a fixed composition

The parts are not spread evenly throughout it

Heterogeneous Mixtures Homogeneous Mixtures

Heterogeneous Mixtures

The parts are noticeably different from one another

You can see the different parts Salsa Sand M&Ms Mixed Vegetables

Homogeneous Mixtures

Difficult to distinguish the different parts Appears to contain only one substance

Tap Water Kool-Aid Air

Mixture Types

Based on the size its largest particles, a mixture can be classified as a Solution Suspension Colloid

Mixture Types

Solution – Substances dissolve and form a homogeneous mixture Sugar and Water

Suspension – A heterogeneous mixture that separates into layers “Shake well before using”

Colloid – Mixture of a suspension and a solution Milk