© Weston, 2009. Physical Properties of Matter So many ways to describe matter!

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© Weston, 2009

Transcript of © Weston, 2009. Physical Properties of Matter So many ways to describe matter!

© Weston, 2009

Physical Properties of Matter

So many ways todescribe matter!

#1 What’s your job during these notes?

1. Pay attention. You’ll learn nothing if you daydream, do otherstuff, or spend 5 minutes in the bathroom.

2. Write notes as we go along. For now, you’re not responsible fordeciding what to write—that will be done for you. However,you should write neatly so that you can read these notes later.

3. Ask questions if you’re confused or want clarification. Telling meabout your new puppy might not be our best use of time, but on-topic discussions will help everyone in the class.

4. Follow the class expectations so that we have a nice & easy timedoing this.

#2 Let’s get started on your paper. Write your heading

Let’s titlethis.

Notes – Physical Properties

Now here’s the important part. To makethis set of notes useful to you, it has tobe neat & organized.

Let’s get started here.

#3 What are Physical Properties?

Well, we know that all matter has mass (it’s made of stuff) and ithas volume (takes up an amount of space).

It doesn’t matter if it’s a flea or a whale

…it’s made of matter. The most enormous stars and the tiniest,microscopic air molecules are matter, too.

#4 Yes, and…?

But matter has properties beyond just “mass” and “volume,” right?

I mean, after all, if I asked you to describe this object here:

…you wouldn’t just tell me, “It has a mass of 34grams and a volume of 23 milliliters.” You’d usewords like delicious, gooey, yummy, soft, smellsgood, and so on and so on.

Well, as nice as it would be to just use whateveradjectives we wanted to describe matter, there are a few that we use allthe time that count as physical properties.

This is the important part…if it’s a way to describe a substance WITHOUT changing it into a new substance, it’s a physical property!

#5 DefinitionNotes – Physical Properties

I like to write notes insomething calledoutline form. It’s a way to use numberingand lettering to seehow things are groupedand related. You’llget the hang of it—just be careful withyour indents for now!

I. Physical Properties – descriptions of matter that can be observed without changing it into a new substance.

Notice how I use underlines to make points of emphasis…thishelps to really make a point to yourself if you read these noteslater.

The Roman Numeral I lets you knowthis is the first major topic in thesenotes.

#6 DENSITY

Density is a weird one. You know by now that all matter has massand volume. But density tries to describe how “packed in” the massis within that volume. In other words, how compact is the stuff?

This golf ball and marshmallow are about the same size (volume).But which is going to have more mass?

The golf ball has way more mass.Since they’re about the same size,you know that the golf ball hasa higher density.

#7 Density, contd.

What’s heavier…a pound of steel or a pound of feathers?Well, a pound is a pound, so they have the same weight. But whatwould those two piles of objects look like?

Hi, Joe. Yo.A pound of steel, yeah.

And a pound of feathers.It’s clear steelis WAY moredense thanfeathers.

#8 More on Density

Don’t forget!

Gases and liquids have densitiestoo! That’s why when a lot ofsubstances are put in the samecontainer, they often form layersbased on their densities!

#9 Back to Our NotesNotes – Physical Properties

I. Physical Properties – descriptions of matter that can be observed without changing it into a new substance.

A. Density – describes how compact the matter is in a substance. A bowling ball is more dense than a beach ball.

Since we’re going tostart listing examplesof physical properties,we will indent themand letter them to gounder the RomanNumeral I. Indent about the width ofyour pinky.

#10 COLOR

Well, it might be pretty simple to say that a frog is green or jeansare blue or Joe is red, but there’s some pretty technical reasons for why things have colors.

The point is that you can describe a substance’s color without changingit into a new substance.

#11 Write it!Notes – Physical Properties

I. Physical Properties – descriptions of matter that can be observed without changing it into a new substance.

A. Density – describes how compact the matter is in a substance. A bowling ball is more dense than a beach ball.

B. Color – describes how light reflects off a substance.

#12 LUSTER

Ooohhh…look at that biscuit. Ooohhh…look at this gold ring.

I desire the one on the left for its tastiness. I desire the one on theright for its LUSTER. Luster describes how shiny a substance is.

#12 Get it on your paper!

Notes – Physical Properties

I. Physical Properties – descriptions of matter that can be observed without changing it into a new substance.

A. Density – describes how compact the matter is in a substance. A bowling ball is more dense than a beach ball.

B. Color – describes how light reflects off a substance.

C. Luster – describes how shiny a substance is. A diamond has higher luster than tree bark.

#13 TEXTURE

Some things are smooth.

Others are rough.That’s texture for you.

#14 I’m going to retire the notebook paper for now.

D. Texture – describes the smoothness/roughness of a substance.

#15 ODOR

A substance that gives off an odor, whether good or bad, isn’tbeing changed as it does so!

E. Odor – describes the smell of a substance.

#16 HARDNESS

This one can be a little confusing. You’ve probably heard that thehardest substance on Earth is ___________.

That means that a diamond can cut any othersubstance you can think of, even metals. The only thing that can cut a diamond is a slightly more pure diamond!

However, that doesn’t mean that diamonds arestronger than anything else. I’d much ratherlive in a brick or steel house than a diamondone.

Keep your bricks. I’ll take the diamonds!

#17 Write it!

F. Hardness – describes a substance’s ability to resist shape change. Doesn’t always mean “strength.”

#22 SOLUBILITY

What happens if you take sugar, salt, or kool-aid powder and stir it into water?

But you haven’t made a new substance. The kool-aid and water havejust mixed super well because the kool-aid dissolves so easily in water.

#23 The Kool-Aid and Water are Separate?

Yep. If you had the world’s best microscope, you could see bits ofred kool-aid floating around in clear water. Our eyes just aren’t goodenough to see things that small so it looks like a consistent, red liquid.

If you tried the same thing with rocks, you’d just have a glass full ofwet rocks. Rocks aren’t soluble, but kool-aid is!

K. Solubility – describes how well a substance dissolves in anothersubstance like sugar stirred in water. The sugar and water haveNOT made a new substance!

#24 STATE OF MATTER

A lot of you remembered that matter comes in three states:

SOLIDLIQUID

GAS

Whether a substance is solid, liquid, or gas is a physical property. You can easily tell me what it is without having to change the substance.L. State of Matter – describes whether a substance is solid, liquid, or

gas.

#25 MELTING & FREEZING POINT

At what temperature does an ice cube melt into water?At what temperature does liquid water freeze into ice?

SAME ANSWER! 320 F or 00 Celsius.

This is a property of water…that 00 Celsius is a magical temperaturefor this particular substance. Above this temperature it stays liquid,but below it, it freezes to solid. NOTICE that it is still just a physicalproperty because the water changes, but not into any new substance!

M. Melting & Freezing Point – describes the temperature at which a solid turns liquid or vice versa.

#26 BOILING & CONDENSATION POINT

Likewise, what’s the magic temperature for water at which the liquidbecomes a gas vapor?

Yes, 2120 F or 1000 Celsius.

N. Boiling & Condensation Point – describes the temperature at which a liquid turns gas or vice versa.

#27 Review

All these properties that we described are physical properties.

This just means that they are ways that scientists commonly describesubstances without having to change them into a new substance.

Remember this?You should be able to go down your listof physical properties and decide whichthis cookie has or doesn’t have.

And then eat

it!

#28 And That’s…