P H Y S I C A L S C I E N C E

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Classifying Matter Notes

2 Types of Matter

There are two types of matter we will be discussing.

Pure Substances

Mixtures

Pure Substances

I. Matter that always has exactly the same composition is classified as a pure substance

Every sample has the exact same properties and composition

These substances are considered homogeneous because they are the same throughout

Which one is a pure substance?

2 Types of Pure Substances

1.) Elements: There are about 115 known elements.

An element is a substance that has only one type of atom.

Atoms are the smallest unit of matter.

Element Examples

Element Symbol

Uses/Properties

Hydrogen H Gas, very light, bonds easily

Lead Pb Metal, solid, dark, poisonous

Potassium K Very reactive, keeps muscles from cramping

Mercury Hg Liquid metal, very dense, toxic

Calcium Ca Metal, strong bones & teeth

2 Types of Pure Substances

2.) Comp0unds: A compound is pure substance that is made of atoms bonded together

Compounds

The compound always has two or more elements joined in a fixed proportion

The smallest part of a compound is a molecule

Examples of compounds are sugar, salt, water

Sugar

Salt

Water

Compounds

The properties of a substance differ from the substances from which it is made.

For example, salt

(sodium chloride, NaCl)

Properties of sodium: yellow, soft metal, very reactive

Properties of chloride: yellow/green toxic gas

Comparing Types of Pure Substances

Comparing Types of Pure Substances

2 Types of Matter

2.) Mixtures:

The composition of a mixture is NOT fixed

Properties of a mixture can change

The parts of a mixture are NOT evenly distributed

Types of Mixtures

There are two main types of mixtures: Homogeneous and Heterogeneous mixtures

1.) Heterogeneous mixtures- Parts of the mixtures are different from one another

It is easy to see the different parts.

Heterogeneous Mixtures

Sand at the Beach

Pizza

Soil

Chocolate Chip Cookies

Types of Mixtures

Homogeneous mixtures- Substances are evenly distributed

It is difficult to distinguish one part from the other

Homogeneous Mixtures Examples

Vegetable Oil

Perfume

Mouthwash

Distinguishing between heterogeneous and homogeneous mixtures.

Sometimes it is difficult to classify mixtures as either heterogeneous or homogeneous

An easy way to classify them is based on the size of the particles that make them up.

Solutions, suspensions, and colloids

Solutions

Solutions: when substances dissolve to form a homogeneous mixture.

There are two parts of a solution: Solvent: substance that does the

dissolving Universal solvent is water

Solute: substance that gets dissolved

Example of a solution: Kool-Aid Liquid solutions do not settle over

time.

Suspensions

Suspensions: a heterogeneous mixture that separates into layers over time.

Rule of thumb for a suspension: Instructions say to “Shake well before use.”

Examples of a suspension: Italian Salad Dressing

Colloids

Colloids- Contain some particles that are intermediate in size between the small particles in a solution and the larger particles in a suspension

Colloids

Examples of colloids are: fog

mayo

Comparing Solutions, Colloids, & Suspensions

Which is which?

A B C

Classifying Matter Concept Map

Element, Compound, or Mixture?

Copper

Element, Compound, or Mixture?

Copper

Element, Compound, or Mixture?

Jelly Beans

Element, Compound, or Mixture?

Jelly Beans

Element, Compound, or Mixture?

Table Sugar

Element, Compound, or Mixture?

Table Sugar

Element, Compound, or Mixture?

Aluminum

Element, Compound, or Mixture?

Aluminum

Element, Compound, or Mixture?

Pure Water

Element, Compound, or Mixture?

Pure Water

Element, Compound, or Mixture?

Lemonade

Element, Compound, or Mixture?

Lemonade

Element, Compound, or Mixture?

Silver

Element, Compound, or Mixture?

Silver