7/22/14Pg. 19 in ILL

Properties of Matter Notes

Matter is defined as anything that has mass and takes up space.

It is made up of atoms.

These atoms have certain ways they behave, look feel, smell, etc.These are known as properties.

There are 3 main states of matter: solid, liquid, and gas.

What is Matter?

A physical property is a characteristic of a substance that can be observed without changing the substance.

It’s important to use all senses when describing physical properties.BE CAREFUL WITH TASTE!!

Physical Properties

a. color (ex. black, red, colorless)

b. shape (ex. square, round, irregular)

c. odor—does it have a smell or is it odorless; description could be compared to something known (ex. rose, lemon, vanilla, etc.)

Examples of Physical Properties

d. magnetism—can it draw, pull, or repel substances on its own

e. hardness—is it rigid or resistant to pressure; is it easily scratched

f. texture—what it feels like (ex. smooth, rough)

Examples of Physical Properties (cont.)

g. luster—the ability to reflect light (ex. dull, shiny)

h. malleability—the ability to be reshaped or rolled out by pounding

i. mass—amount of matter in an object; measured in grams

Examples of Physical Properties (cont.)

A physical property of a substance that does not change based on the amount of the substance is known as a characteristic property.

Characteristic properties can be used to identify unknown substances.

Characteristic Properties

a. density—the amount of mass per unit volume

formula:

density = mass/volume

(D = M/V)

units: g/mL (for gases and liquids)

g/cm3 (for solids)

Examples of Characteristic properties

b. the temperature at which a substance changes states

boiling point—the temperature at which a liquid starts changing to a gas

melting point—the temperature at which a solid melts to become a liquid; same temperature as the freezing point of a substance

Why is mass not an example of a characteristic property?

Examples of Characteristic properties (cont.)

Properties that can only be observed by changing the original substance into a new one are called chemical properties.

These cannot be determined by just viewing or touching the substance.

Chemical properties

a. flammability—how easily a substance will burn or ignite

b. oxidation—when some substances are exposed to oxygen, they chemically react with it to form rust, the brown on a cut apple, etc.

c. pH—how acidic or basic a substance is when dissolved in water

Examples of chemical properties

When the same substance is present before and after a change, it is known as a physical change.

Examplesa. melting iceb. cutting hairc. crushing a cand. breaking glasse. tearing paper

Physical vs. chemical changes

A chemical change takes place when a new substance with new properties is formed during the change.

This type of change takes place when a chemical reaction occurs.

Examplesa. burning woodb. cooking an eggc. a nail rusting

Physical vs. chemical changes (cont.)