Matter & ChangeNotes

Terms to Know

A. Chemistry- The study of MATTER and the CHANGES it undergoes.

Terms to Know

B. Mass- a measure of the amount of matter.

C. Matter –anything that takes up space and has mass.

Terms to Know

Three phases of matter:

solid – has definite shape and definite volume

liquid – NO definite shape; definite volume

gas – NO definite shape; NO definite volume

Wait a minute! I have heard of a 4th state matter-

PlasmaPlasmas are a lot like gases, but the

atoms are different because they are made up of free electrons and ions of the element.

Plasmas are a high-temperature state of matter in which atoms lose their electrons. Not naturally found on earth

Terms to Know

D. Atom– the SMALLEST particle of an element that retains the chemical properties of the element

E. Element- a pure substance

made of ONLY ONE kind of atom from the P. T. (ex: C, N, O)

Terms to Know

F. Compound- composed of 2 OR MORE elements from the P. T. in a fixed ratio

– properties differ from those

of individual elements

EX: table salt (NaCl)

Terms to Know

G. Law of Definite Composition – the elemental composition of a pure compound is always the same regardless of where or how it is prepared.

• Consider the compound water: H2O

– There are always 2 Hydrogen atoms for every 1 Oxygen atom, never 3 Hydrogens for every 1 Oxygen… then it wouldn’t be water!

II. Properties and Changes in Matter

A. Physical Properties of Matter characteristics which allow us to recognize and distinguish it from another substance WITHOUT changing the substance!

– Examples of physical properties are color, odor, density, melting and boiling points and its physical state (solid, liquid, gas)

A. Properties and Changes in Matter

Intensive property – does NOT depend on amount of substance present; is constant, examples are density, melting or freezing points, heat capacity, solubility

Extensive property – DOES depend on amount of matter present. Ex: mass, volume

Learning Check Are the following examples intensive or

extensive properties?• Examples:

1. Boiling point

2. Melting point

3. color

4. Odor strength

5. mass

intensive

intensive

intensive

extensive

extensive

II. Properties and Changes in Matter

B. Physical Changes of matter– do not involve the creation of a new substance. Ex: grinding; the physical state of a substance is changed.

II. Properties and Changes in Matter

• Know these 6 phase changes:

– Melting: Solid to liquid

– Evaporation/Boiling: liquid to gas

– Condensation: gas to liquid

– Freezing: liquid to solid

– Sublimation: solid to gas

– Deposition: gas to solid

States of Matter

• http://www.youtube.com/watch?v=xYFAj50c7xM

Any change in state is a physical change…

A physical change is usually REVERSIBLE!!!

II.Properties and Changes in Matter

C. Chemical Properties – the manner in which a substance reacts with another substance to make a NEW substance!

Ex: hydrogen and oxygen gases react to form water where hydrogen and oxygen are the reactants and water is the product.

Write this down!

H2 + O2 H2O

Reactants Products

D. Chemical Changes of Matter

Involves changing one

substance into a NEW substance: cannot get the original substance back: burning, fermentation, cooking a steak, etc. A chemical change is

a chemical reaction.

5 Signs of a Chemical Reaction

• There are five indicators that a chemical reaction has taken place.

• They are…1. Color change2. Temp. change3. Gas.4. Appearance of a

precipitate (solid)5. Light.

Is this a chemical or physical reaction? How do you know?

• http://www.youtube.com/watch?v=SJCcH0ATMQ4

II. Properties and Changes in Matter

1. Reactants: to the LEFT of the arrow

2. Products: to the RIGHT of the arrow

Mg + 2 HCl MgCl2 + H2

Reactants products

Learning Check Are the following examples physical or

chemical properties?• Examples:

1. rusting iron

2. dissolving in water

3. burning a log

4. melting ice

5. grinding spices

chemical

physical

chemical

physical

physical

Card SortGo to the next blank page in your journal. It should be titled “Examples of Physical and Chemical Changes”. Make a T Chart with the titles of Physical on one side and Chemical on the other. Copy the information on the next two slides in the appropriate column.

Physical/ Chemical Changes

Physical Changes• Does NOT produce a

new substance• Is REVERSIBLE

Chemical Changes• Produces a new

substance• Is NOT reversible

Physical/Chemical Properties

Physical Properties• Does NOT require

altering the material• Does NOT require a

chemical change

Chemical Properties• Requires altering the

material• Requires a chemical

change

Card SortGo to the next blank page in your journal. It should be titled “Examples of Intensive and Extensive Properties”. Make a T Chart with the titles of “Intensive” on one side and “Extensive” on the other. Copy the information on the next slide in the appropriate column.

Intensive/Extensive Properties

Intensive Properties• Does NOT depend on

the amount of matter

Extensive Properties• Does depend on the

amount of matter