P. Sci.

1
P. Sci.

• Unit 7
• Chapter 2
• Matter

2
Chemistry

• What things are made of and how things change.

3
Matter

• Has mass and takes up space.
• Matter is made up of atoms
• Light sound and electricity are NOT matter

4
Atoms

• The smallest particle that
• has the properties of
• an element.
• Element a substance that cannot be broken down
  into simpler substances.

All the atoms in the substance are alike
5
Elements

• Each element has a one or two letter symbol used
  worldwide to designate it.
• The chart that shows
• all the known elements
• is called the Periodic
• Table of Elements.

6
Compounds

• When two or more elements combine chemically you
  get a compound.

7
Molecule

• The smallest unit of a substance that exhibits
  all the properties of that substance.

8
Chemical formulas

• The combination of chemical symbols (and how many
  atoms of each) make up a molecule of a substance.

9
Pure vs. Mixtures

• Pure substances any substance that has a fixed
  composition and definite properties.

Table sugar C12H22O11
10

• Mixtures - A combination of substances that are
  not fixed
• they can change

OJ is a mixture of water, citric acid and sugar
among other things. Any drop of Orange Juice can
have different amounts of the different
components.
11
Classifications of Mixtures

• Homogeneous Mixtures a mixture that is the same
  throughout (completely mixed)
• Heterogeneous Mixtures a mixture where you can
  see all the parts. (incompletely mixed)

12
Properties of Matter

• Physical Properties
• Chemical Properties
• Physical Changes
• Chemical Changes

Changes of Matter
13
Physical Properties

• characteristics of a material which can be
  observed without changing the identity of the
  substances in the material.
• examples include color,
• shape, size, melting
• point, and boiling point.

14

• Appearance physical description of a substance.
• Behavior how a substance acts for example,
  magnetism, viscosity, ductility.
• Physical properties such as size and magnetism
  can be used to separate mixtures.

15
Chemical Properties

• Characteristics of a substance
• indicating that it can change
• chemically.

16

• Examples flammability or light sensitivity of a
  substance, production of a gas, production of a
  precipitate, change in odor.

17
Physical Change

• A change in a substances physical property
  (properties).
• Substance does not change identity when it
  undergoes a physical change.
• Examples change in size, shape, or state of
  matter

18
Chemical Change

• When one substance changes to another substance.
• Some chemical changes are indicated by
  temperature change, smell, or bubble formation.

19

• Other chemical changes occur very slowly such as
  the formation of rust.

20
Density

• The mass per unit volume of a substance.
• (how much matter is packed into a specific
  amount of a substance)
• d m/v
• Density is a physical property.

21
Dissolving

• When a substance dissolves, it seems to disappear
  because the particles of the substance spread out
  between the particles of the liquid. Neither
  substance changes into another substance,
  therefore
• Dissolving is a physical change.

22
Change of State

• When a substance goes from one state of matter to
  another the substance does not change into
  another substance. (ice, water, steam are all
  H2O)
• Therefore Change of State is a Physical Change.

23
End of Part 1