Physical Properties of Matter

Chapter 9Lesson 1

What is Matter?

• Everything that makes up the world around you.

• Anything that has mass and volume.

http://www.youtube.com/watch?v=s-KvoVzukHo

• http://www.youtube.com/watch?v=tBQcpF_j5Xg&feature=related

Mass

• The amount of matter in an object.– Measured in grams or kilograms

Order from most mass to least

Weight

• The amount of pull of gravity between an object and Earth.– Objects with more mass weight more.

• Balances are used to measure an object’s mass by allowing gravity to pull the object down.

Volume

• The amount of space taken up by an object.– Measured in Cubic centimeters • The volume of a cube that measures 1 cm on each side.

– The volume of an object equals the number of cubes it takes to fill that object.

Graduated Cylinders

• Used to find the volume of a liquid or a solid.– Measured in milliliters (mL)

Volume of a liquid

• Pour a liquid into a graduated cylinder.• To read the volume, read the number that is below the curved line or meniscus.

Volume of a solid

• Water displacement• Put water into a container with measurements

and record the measurement.• Place the solid into the container with water.• Measure where the water level rises to.• The amount the water rises is the solid’s

volume.

Measuring Density

Which one of these solids is more dense?

What is density?

• Density is how much matter is packed into a certain space of an object. • The units we use for density are g/cm3 if

we’re measuring a solid and g/mL if we’re measuring a liquid.

Divide

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How do we calculate density?

• Density is calculated using the formula D = M/V– Density is mass divided by volume.

• If we know 2 of these numbers, we can calculate the 3rd.– Remember this triangle:

D = DensityM = MassV = Volume

Department of Motor Vehicles

D = M/VM = D x VV = M/D

Let’s try some practice problems

1. The density of a shell is 1.2 g/cm3 and the volume is 10 cm3. What is its mass?

2. The mass of a rock is 450 g and its volume is 15 cm3. What is its density?

3. The mass of an element is 32 g and its density is 4.0 g/cm3. What is its volume?

Density of water

• Water has a very special property. How much mass does 1 mL of water have? – If 1 mL of water has a mass of 1 g, what is its

density?– We can use this number to determine whether

something will float on water or not by finding the object’s density and deciding if it is greater than or less than 1.

Why is it important to know the density of a solid or liquid?

The density of a solid or a liquid is used to identify it. –Example: every piece of gold has a

density of 19.3 g/cm3

Physical Properties• can be observed or measured without

changing the composition of matter.• used to observe and describe matter.

• includes: – Appearance– texture – color – odor– melting point – Boiling point – density– solubility

Physical Changes

• takes place without any changes in molecular composition.

Melting Point• As solid matter is heated it eventually melts or

changes into a liquid state at the melting point.

• http://www.cleanvideosearch.com/media/action/yt/watch?videoId=foQhHfsyPIc

Boiling Point

• As the liquid matter is heated further it eventually boils or vaporizes into a gas at the boiling point.

• http://www.youtube.com/watch?v=WIOlnXbRpuk

• http://www.youtube.com/watch?v=w5Y452eiHC8

Day 2

Mixtures• Any combination of two or more substances in which the substances keep their own properties.

• Some substances properties are not always recognized in a mixture.

Types of Mixtures

Suspensions Alloys

Colloids Solutions

• http://app.discoveryeducation.com/search?Ntt=mixtures

Suspensions

• Made of parts that separate upon standing.

• Emulsion– The short time the substances are mixed together

Colloids• Contains undissolved particles or droplets that

stay mixed in another substance. liquid water Fog = droplets or ice crystals suspended in the air Smoke = a collection of airborne solid and liquid particulates and gases

Solutions• A mixture of one substance dissolved in

another so the properties are the same throughout.

All parts have the same properties such as color, odor, and taste.

Parts of a Solution• Solute – the substance that becomes dissolved.

• Solvent – the part that dissolves a substance.

• Mixture – Hot chocolate!

Solubility

• the property of a solid, liquid, or gas (solute) to dissolve in a solid, liquid, or gas (solvent) to form a solution.

Alloys

• A solid solutions of one or more metals and other solids.• How they are made:

1. heating, melting, and mixing the parts together. 2. The solution cools and hardens.3. The parts remain dissolved in each other in the

solid phase.

• http://app.discoveryeducation.com/search?Ntt=suspension+mixture

Why Do Things Float?

Buoyant Force• An object is submerged in a fluid.• The fluid “pushes” in on the object.• The push is greater on the bottom than the

top, so the fluid actually pushes the object towards the surface.

• http://app.discoveryeducation.com/search?Ntt=buoyancy

• http://app.discoveryeducation.com/search?Ntt=buoyancy

• http://app.discoveryeducation.com/search?Ntt=buoyant+force

Displaced Water

• Objects with more weight than buoyant force will sink.

• Objects that displace a weight of fluid equal to their own weight will float.

“Egg”speriment

• An uncooked egg will sink to the bottom of a beaker of water. • If the water is mixed with something, the egg

will be able to float. • What can we mix the water with to create a

force to push the egg up?• When we mixed ______ with water, how did

that enable to egg to float?