Properties of MatterProperties of Matter

Physical Properties, Phases of Physical Properties, Phases of Matter, Chemical PropertiesMatter, Chemical Properties

General (Physical) Properties

Physical properties may be observed without changing the nature of the matter.

Boiling point is a physical property When a liquid boils, the

vapor may be condensed to get the liquid back

The liquid is still the same substance

What are some Physical Properties?

Properties you can see, such as color, shape, hardness, and texture

Properties that are easily measured, such as mass, volume, density, melting point, boiling point Note! Freezing and melting point are the same

temperature! Density = Mass ÷ Volume

Is the ability to be attracted to a magnet a physical property?

How do we measure mass and How do we measure mass and volume?volume?

Mass is measured on a balance or Mass is measured on a balance or scale. Common units are grams, scale. Common units are grams, milligrams, and kilogramsmilligrams, and kilograms

Liquid volume is measured with a Liquid volume is measured with a graduated cylinder. Common units are graduated cylinder. Common units are liters and millilitersliters and milliliters

Solid volumes may be calculated with Solid volumes may be calculated with formulas or by water displacement formulas or by water displacement Common units are cmCommon units are cm33 or milliliters. or milliliters.

Finding Volume by Water Displacement

A wooden block raises the level of the liquid in the graduated cylinder from 150ml to 180ml. What is the volume of the block?

180ml – 150ml = 30ml

M

D I V

If the density of the block is 300g/ml, what is its mass? (remember, its volume was 30ml)

M

300g/ml I 30ml

9000g

Measuring Volume with a Formula

A wood block as in the last example has sides that are 2cm wide, 5cm long, and 3cm high. What is the volume of the block?• Use the formula l x w x h

• The answer will be in cm3

If its mass is 90 grams, what is its density?

2cm x 5cm x 3cm 2cm x 5cm x 3cm = = 30cm30cm33

90g ÷ 30cm3 = 3g/cm90g ÷ 30cm3 = 3g/cm33

Let’s Try Some More Density Problems

1) If the mass of a rock is 500g and its volume is 25cm3, what is its density?

2) If the density of a liquid is 1.2 g/ml, and its volume is 10ml, what is its mass?

3) If Bob’s mass is 80kg and his density is 1.6kg/l, what is his volume?

Answers: D = M ÷ VAnswers: D = M ÷ V

1) 500g ÷ 25cm1) 500g ÷ 25cm3 3

= 20g/cm= 20g/cm3 3

2) 1.2g/ml x 10ml 2) 1.2g/ml x 10ml = 12g= 12g

3) 80kg 3) 80kg ÷ 1.6kg/l ÷ 1.6kg/l = 50L= 50L

M

D V

WEIGHT Weight is the pull of gravity on mass. Weight changes in response to gravitational

pull. A person’s mass will remain the same on

the earth or on the moon, but she will only weigh 1/6 as much on the moon.

PHASES OF MATTERPHASES OF MATTER

The most common phases of matter are The most common phases of matter are solid, liquid, and gassolid, liquid, and gas

Plasma is a high energy phase found in Plasma is a high energy phase found in starsstars

When a substance changes phase, energy When a substance changes phase, energy (heat) is lost or gained, but temperature (heat) is lost or gained, but temperature remains the same.remains the same.

The northern lights are caused by plasma streams fromthe sun hitting our atmosphere. This causes electrons inatmospheric gases to be excited to a higher energy level,And when they drop back down, a photon of light is emitted.

Types of Phase Changes

• Solid to liquid:

Melting• Liquid to gas:

Vaporization• Gas to liquid:

Condensation • Liquid to solid:

Freezing• Solid to gas:

Sublimation

Temperature Doesn’t Change During Temperature Doesn’t Change During a Phase Change!a Phase Change!

Chemical Properties and Changes

• Chemical properties describe a substances’ ability to change into a different substance. A chemical change is the process by which the substance changes.

Examples of Chemical Properties

• Flammability• Ability to support burning• Ability to combine with other

chemicals in a chemical reaction.

Examples of Chemical Changes

• Rusting• Photosynthesis• Explosions• Burning• Digestion• Baking food• Fermentation

What are indicators of a chemical change?

• Gas given off• Heat absorbed or released• Light given off• Color change• Oxidation of a metal• New substances are formed