CHEMISTR

YWARM UP- What are the physical properties of matter?Hint: There are 7 of them!

IMPORTANT VOCABULARY

Chemistry

Matter

Scientific Method

Mass

Substance

Physical Property

Solid

Liquid

Gas

Vapor

Physical Change

WHAT IS CHEMISTRY?

Chemistry is the study of the composition of MATTER!

Chemistry is a SCIENCE!

In order to study ANY science, the Scientific Method must be used!

The Scientific Method involves following certain steps to come to a conclusion about the natural world

SCIENTIFIC METHOD

WHY?!?!

The scientific method is the standard approach to solving questions related to science

By using the scientific method, scientists can reach conclusions that help form a theory, and maybe even a scientific LAW!

Unfortunately, not all theories can be proven, but those that can become scientific law

MATTER

Since chemistry involves studying matter, what exactly IS matter?

Matter is anything that has mass and takes up space

This even includes AIR!

We measure matter by observing its mass.

We observe matter by observing and describing its physical properties

PHYSICAL PROPERTIES

A Physical Property is any characteristic of a substance that can be observed or measured WITHOUT changing what it is made of

Color

Solubility

Odor

Hardness

Density

Melting Point

Boiling Point

PHYSICAL PROPERTIES OF COMMON SUBSTANCES

Substance

Formula

State Color Melting Point (oC)

Boiling Point (oC)

Density (g/cm2)

Gold Au solid gold 1064.43 2807.0 19.32

Water H2O liquid colorless 0 100 1.00

Sodium Chloride

NaCl solid white 801 1413 2.17

Sucrose C12H22O11 solid white 185 * 1.59

Oxygen O gas colorless -218 -183 0.0014

STATES OF MATTER

BREAKOUT

Pick a partner! (ONLY 1!)

I have filled a plastic bag with water. I will poke a pencil through it. Using the scientific method (ALL OF THE STEPS),

describe the experiment and what happened.

MIXTURES

A mixture is a blend of substances. There are 2 types.

Homogenous mixtures- completely uniform composition (looks the same throughout)Heterogeneous mixtures- not uniform in composition (components not evenly distributed throughout)

Another name for a homogenous mixture is a SOLUTION

Example: Air, salt water

In heterogeneous mixtures, there are2 or more phases Any part of the mixture that DOES have a uniform composition is a phase

Example: Oil and Vinegar

HOW DO WE SEPARATE MIXTURES?

Simply- we can pick out the pieces

More complicated- we can use the different physical properties of each

Method

Filtration

Distillation

Decanting

Chromatography

FILTRATION

Using a filter to separate two substances

Example: Cooking pasta

DISTILLATION

Heat the mixture until it boils

Collect the steam, and cool the steam so it condenses into a more pure liquid

Example: salt water

DECANTING

Pour off separate layers of the mixture

Example: Oil and Water

CHROMATOGRAPHY

Lots of different types!

Paper chromatography is pretty common and easy to do!

BREAKOUT

Grab a partner (only 1!)

1. Is it a homogenous mixture, heterogeneous mixture, or a pure substance?

Silver

Soup

Salad

Sand

Air

Apple juice

2. How might someone separate a mixture of salt and pepper?

LABORATORY EQUIPMENT