what’s the matter?. physical properties of matter so many ways to describe matter!

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What’s the Matter?

Physical Properties of Matter

So many ways todescribe matter!

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.

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!

Properties of Matter: 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.

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.

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!

Properties of Matter: 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.

Properties of Matter: 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.

Properties of Matter: TEXTURE

Some things are smooth.

Others are rough.That’s texture for you.

Properties of Matter: ODOR

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

Odor – describes the smell of a substance.

Properties of Matter: 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!

Some substances allow forms of energy,such as heat, sound, and electricity, to flowthrough them very easily. Apparently, Joeis one of those substances.

These substances are very useful for thingslike:

Properties of Matter: CONDUCTIVITY

Conductivity, contd.

But other substances are useful to us because they’re NOT good conductors. We call those insulators.

Conductivity – describes how well a substance allows heat orelectricity to flow through it. Low conductivity substances arecalled “insulators.”

Properties of Matter: MALLEABILITY

What do these substances have in common?

If you said that they can be pounded with a mallet or hammer or fistor forehead into new shapes easily, then you’re right!

Malleability – describes how easily a substance can be formed intonew shapes. Opposite of “brittle.”

Properties of Matter: DUCTILITY

What do THESE substances have in common?

Well, of course…they’re all ductile! That just means they can be stretched or drawn into wires without falling apart or breaking.

Ductility – describes how well a substance can be pulled into thinwires.

Properties of Matter: MAGNETISM

I’m not sure how much to say about this. Some substances are magnetic,others aren’t.

Magnetism – describes if a substance attracts or repels magnets.

Properties of Matter: 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.

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!

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

STATES 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.State of Matter – describes whether a substance is solid, liquid, or

gas.

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!

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

BOILING & CONDENSATION POINT

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

Yes, 2120 F or 1000 Celsius.

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

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!

Categories of Matter

Pure Substance

• A pure substance is any single type of material.• It cannot be separated into components by physical

separation methods, i.e. without breaking chemical bonds.

Element

• Consist of only one type of atom• Many elements are found in nature and so may

be called "naturally occurring elements".

Examples of Elements

Compound

• Consist of atoms of two or more different elements bound together chemically,

• Can be broken down into a simpler type of matter (elements) by chemical means; but not by physical means

• A compound is a pure substance that consists of two or more elements chemically combined

Examples of Compounds

Mixture

• Consist of two or more different elements and/or compounds - physically intermingled,

• Can be separated into their parts by physical means (e.g. distilation of liquids or seperating magnetic and non-magnetic solids using a magnet).

Examples of Mixtures

ECM Chart

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