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Chemical and Physical Properties and Changes

Matter

• Matter is everywhere. • Matter is anything that takes

up space and has mass. • Matter is constantly

experiencing both chemical and physical changes.

Physical Properties and Changes

Physical Properties are used to observe or describe matter.

How do you observe or describe someone?

•Height•Hair Color•Eye Color•Weight•Age•Clothing Color

Let’s describe Dwight Schrute

Physical Properties and Changes

When we observe or describe something or someone we use “drivers license” descriptions.

When we observe or describe MATTER we use some of the same

descriptions.

List as many

physical properties

as you can…

Physical Properties and ChangesThings you observe and can describe about matter:

• Color• Size

• Smell• Freezing Point• Melting Point

• Mass• Shape

• Volume• Density

Physical Change

• Physical changes occur when matter changes its property but not its chemical nature.

• Physical property changes could include a change in: texture, shape, size, color, odor, volume, mass, weight, and density.

Physical Properties and Changes

• Do NOT change the structure of matter when they are observed or described.

• What does “structure” mean?

How the atoms are stuck together!

Each letter is a different atom, and

the lines that connect the letters show the STRUCTURE of the

substance.

And here each color represents a different atom and this picture shows the STRUCTURE of the substance.

Physical Properties and Changes

• What is the “structure” of water?

• What is the “structure” of ice?

• What is the “structure” of steam?

Physical Properties and Changes

• We just observed one of the physical properties of H2O!

PHASE CHANGEWe observed how H2O is different in

each phase, but the structure of H2O never changed!

Physical Change

The difference between Physical Property and Physical

change.

• The physical property is something that we can measure with out changing the identity of the matter. That includes the materials ability to change shapes but not change what it is

• The physical change is the actual process of changing shapes. Remember that no new substance it formed!

Physical Properties and Changes

When a physical property (like the phase of water) is altered we called it

a PHYSICAL CHANGEIn other words: A physical change

involves a change in physical properties (shape, size, density, etc.)It takes a physical change to change

water to steam, or ice to liquid.

What are some other examples of physical changes?

Physical Properties and Changes

• Shape

The shape of the wood changed. But is it still a piece of wood?

Physical Properties and Changes

• Shape

Physical Properties and Changes

• Color

The tip of the nail changed color. But is it still a fingernail?

Physical Properties and Changes

• Melting Point

The ice cream melted. But does it still taste like ice cream?

Physical Properties and Changes

You can think of Physical Changes like changing the font of a word…

Mr. ArchibaldMr. ArchibaldMr. ArchibaldMr. ArchibaldMr. Archibald

The “structure” of the words is still the same, even though the physical

appearance changed.

Chemical Change

• Chemical changes are changes matter undergoes when it becomes new or different matter.

• To identify a chemical change look for signs such as color change, bubbling and fizzing, light production, smoke, production of odor, and presence of heat.

Chemical Properties and Changes

• And you can think of Chemical Changes like rearranging the letters

of the words…Mrs. CoatesMost AcresCream TossRe: MascotsMe Toss CarCares Most

Chemical Properties and Changes

The letters are the same, but we’ve rearranged the structure and made

new words!

This is what happens in a chemical change!

Chemical properties lead the way for chemical change

Chemical Properties and Changes

What are some examples of Chemical Properties?

• Flammability• Oxidation• Toxicity• Radioactivity• Sensitivity to Light• Reactivity with water

Chemical Properties and Changes

• Flammability:– The ability to catch fire!

Chemical Properties and Changes

• Oxidation– The ability to react with Oxygen

Chemical Properties and Changes

• Toxicity– The ability to be poisonous

Chemical Properties and Changes

• Sensitivity to Light– The ability to change when exposed to

light

Chemical Properties and Changes

• Reactivity with water– Some elements react explosively with

water!– Sodium, Potassium, Lithium, and

Calcium

Chemical Change

• A chemical change occurs when fireworks are used. Fireworks are made of metals such as magnesium and copper. These change chemically as they light up the sky.

Examples of Chemical changes

• Soured milk• Alka seltzer• Statue of liberty being eroded by

acid rain• Space shuttle launch

Chemistry & Chemistry & MatterMatter

• We can explore the We can explore the MACROSCOPIC MACROSCOPIC world — what world — what we can see — we can see —

• to understand the to understand the PARTICULATEPARTICULATE worlds we worlds we cannot see.cannot see.

Kinetic Nature of MatterKinetic Nature of MatterKinetic Nature of MatterKinetic Nature of MatterMatter consists of atoms and molecules in ____.Matter consists of atoms and molecules in ____.

The In-Betweens: Physical or chemical?

• Some properties (abilities) can be either physical or chemical

• Examples:–Ability to change color–Change in temperature

Both of these examples are making a gas. Which one is physical and which is

chemical?

Both of these pictures show a color change due to heat: which is physical and which is

chemical?

Lets Take the QUIZ…

•http://vital.cs.ohiou.edu/steamwebsite/downloads/ChangeLab.swf

1. Is it a chemical or physical change?

• Sugar dissolving in tea

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

2. Is it a chemical or physical change?

• Logs burning

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

3.Is it a chemical or physical change?

• Breaking water up by separating it into hydrogen and oxygen

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

4.Is it a chemical or physical change?

• Cutting paper

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

5.Is it a chemical or physical change?

• Crushing an aspirin

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

6. Is it a chemical or physical change?

• Metal rusting

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

7.Is it a chemical or physical change?

• Lighter fluid burning

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

8.Is it a chemical or physical change?

• An egg rotting

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

9. Is it a chemical or physical change?

• An egg breaking

•Chemical Change

•Physical Change

OOPS!

Did it change size, color, shape (Physical Change)?

orDid it become different matter

(Chemical Change)?

Correct!

Writing Activity

• Write a paragraph about the difference between a chemical and physical change. Give examples of each.

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