MATTER

Matter – has mass & occupies space – 1:25

I. Properties of Matter

A. Physical prop. – any characteristic that can be observed or measured without changing the material;

Ex. color, mass, volume, length, density, shape, taste, odor, texture, hardness, conductivity, melting/ boiling points, metal, nonmetal, states of matter

Physical Properties – 3:39

States of Matter1. Solid – particles close together; low energy;

definite shape & volume

2. Liquid – particles medium distance & energy; no def. shape & def. volume

3. Gas – particles far apart; high energy; no definite shape or volume

(Plasma – occurs at high

temps.)

States of Matter – 4:35

B. Chemical prop. – characteristic that allows a substance to change to a new substance

Ex. flammability (burning) – paper, wood, oxygen

rusting (reaction) – iron

tarnishing (reaction) – silver, copper

reactivity (reacts w/other substances) – vinegar w/baking soda; sodium + water;

Chemical Properties – 1:16

II. Changes of Matter

A. Physical changes – only changes what the substance looks like; not something new

Ex. separating substances – (ex. coins)

crushing/grinding – making smaller

change of state – melting/freezing

B. Chemical changes – changes to new substance; signs: production of heat, light, smoke, change in color or smell,

Ex. Burning

rusting – Fe + O2 Fe2O3

tarnishing – Ag2O + H2SAg2S + H2O

reactions

Photo. CO2 + H2O C6H12 O6 + O2

Chemical Changes – 6:10

1. How could you change an egg physically?

2. How could you change an egg chemically?

Kitchen Oil Fire

III. 3 Basic Kinds of Matter – elements, compounds, & mixtures

A. Elements – composed of 1 kind of atom; pure - (found on the periodic table)

1. Ex. C, H, N, O, P, S, Au, Ag, Cl, Fe, Ca, Na, He, Ne, Cu

2. Atom – simplest indivisible particle

a. proton: + charge; in nucleus

b. neutron: neutral charge; in nucleus

c. electron: - charge; in shells

Atom looks like:

Protons +

Neutrons

3. Finding # of p+, n, & e- : look at periodic table – different #s give different properties

Top # = # of protons, # of electrons

Bottom # rounded = mass # =

# of protons + neutrons

# of protons = ______

# of electrons = _____

mass # = __________

# neutrons = _______

Ex. Lithium:

3 = 3 p+ / 3 e-

Li

6.941 = round to 7 then

subtract 3 = 4 neutron

Ex. Gold

= 79 p+/ 79 e-

= round to 197 then

subtract 79 = 118 neutron

4. Electrons found in shells – 1st: 2 e- max.

- 2nd: 8 e- max.

- 3rd: 18 e- max.

6 protons

6 neutrons

6 total electrons – 2 in

1st shell & 4 in 2nd shell

Lithium

protons = 3

neutrons = 4

total electrons = 3

2 e- in 1st shell

1 e- in 2nd shell

Practice:

Oxygen:

Sodium:

Aluminum

Structure of Matter – Elements: 2:28

B. Compounds – 2 or more elements chemically combined; can’t be physically separated; pure

1. Have formulas – atoms have definite ratios - NaCl; H2O; CO2; MgO, NH3

(ammonia), C6H12O6 (glucose)

subscript gives you # of atoms of each element –

ex. NaCl : 1 Na & 1 Cl

H2O : 2 H & 1 O

NH3 : 1 N & 3 H

2. Metal elements (left side) combine with nonmetal elements (right side) to form compounds

- metals give up e- to have + charge;

- nonmetals take e- to have - charge

- The different charges must balance out to zero: add subscript #s to have a zero charge

Na: +1 ; Cl: -1 NaCl

Mg: +2 ; Cl: -1 MgCl2

Al: +3 ; F: -1 AlF3

(use cards to make compounds)

3. Compounds go through chemical rxns:# of atoms & mass of reactants must equal # of

atoms & mass of products (law of conservation of matter/mass)

reactants products

2H + 2 O H2O2 (same # of atoms)

2 g H + 32 g O 34 g H2O2 (same mass)

LAW OF CONSERVATION OF MASS/MATTER = mass/matter of the reactants = the mass of the products; mass is neither created nor destroyed

(Don’t have to write this down)

Law of Conservation of Mass/Matter

# of atoms & mass before & after is the same

Cl2 + 2NaBr 2NaCl + Br2

71 g 206 g 117 g + 160g

Fe 2O 3 + 6HCl 2FeCl3 + 3H2O

160 g + 219 g 325 g + ? g

2H2O2 2 H2O + O2

68 g 36 g + ? g

Compounds - 3:59

C. Mixtures – 2 or more substances physically combined; can be separated into pure substances

1. Homogeneous mixture – same composition throughout called a solution (solute = dissolved substance + solvent = dissolver – water is called the universal solvent)

Ex. saltwater (salt is the solute & water is the solvent); air, motor oil, tea

2. Heterogeneous mixture – has different composition throughout:

Ex. muddy water, concrete, granite, lemonade w/pulp, watch

Physical Changes/Mixtures – 6:43

THE END!!