Notes

Unit 3-5 notes pages 128-152

Thermal Contraction- decrease in volume as its temperature decreases

Thermal expansion- increase in volume as temperature increases

Heat- Transfering of thermal energy from region of higher temperature to a region with lower temperature

Pressure- amount of force per unit applied to an objects surface

Vaporization- change in state from liquid to gas

Chemical Formula =

Tells what elements a compound contains and the exact number of the atoms of each element in a unit of that compound.(List the number and kinds of atoms present.)

Chemical Bond =

The force that holds atoms together in a compound

Section 2: Types of Bonds

Ion =An atom that has lost or gained electrons (it is now a charged particle because it now has either more or fewer electrons than protons)

*Superscript =“Written above”

e.g. H+1 (the “+1” is the superscript)

*Subscript =“Written below”

e.g. H2 (the “2” is the subscript)

Ionic Bond =The force of attraction between opposite charges of the ions in an ionic compound

**These bonds are weak as electrons are transferred.**

*Ionic compounds= *Formula Unit -

A compound that results when a metal reacts with a nonmetal to form cations and anions. 

(Do not use the term for the subscript.)

Covalent Bond =

The attraction that forms between atoms when they share electrons

**These bonds are strong as electrons are shared.**

Molecule =

A neutral particle that forms as a result of electron sharing

Polar Molecule =

A molecule that has a slightly positive end and a slightly negative end although the overall molecule is neutral

(e.g. H2O)

Nonpolar Molecule =

A molecule in which electrons are shared equally in bonds

(e.g. CCl4)

Section 3: Writing Formulas and Naming Compounds

 START HERE!

Binary Compound =

A compound that is composed of two elements

(bi- means two)

e.g. KI (Potassium Iodide) (2 different elements)

Oxidation Number =

Tells you how many electrons an atom has gained, lost, or shared to become stable

(written 1+, 2+, 1-, 2-, etc.)

Oxide ion  =2-     Magnesium ion = 2+

Polyatomic Ion =(A group of atoms that have a charge.)

A positively or negatively charged, covalently bonded groups of atoms

e.g. HCO31- (bicarbonate ion)

*Monoatomic ion-

One atom that has taken in or lost an e-1 (electron).

i.e. F1-(fluoride ion)

*Cation – A positively charged ion. 

(Metals in the formula units.)

*Anion – A negatively charged ion.

(Nonmetals in the formula units.)

Hydrate =

A compound that has water chemically attached to its ions and written into its chemical formula

e.g. CaSO4 . 2 H2O(Calcium Sulfate Dihydrate)

# of waters      Name      

1                       Mono   My

2                       Di    Dad

3                       Tri   Tried

4                       Tetra Tetris

5                       Penta

6                       Hexa

7                       Hepta

8                       Octa

9                       Nona

10                     Deca

Naming Formula Units:(Metals from the Shell S and P)

1.Write the name of the first element.

2. Write the name of the second element with the -ide ending.

Example: Name the following:

K2O

Potassium Oxide

Naming Formula Units:(Metals from the Shell d)

1. Write the name of the first element.

2. Write the charge in Roman numerals.

3. Write the name of the second element with the -ide ending.

Ex.What is the name for the following:

MnO

Manganese (II) Oxide

Roman numeral charges

1=I   2=II       3=III      4=IV

****Use this method when naming compounds with 3 or more elements**

Naming Formula Units:(Metals and a polyatomic anion)

1. Follow the rules for naming the metal.

2. Write the name of the polyatomic ion from the polyatomic ion chart.

Ex.  What is the name for the following:

MgCO3

Ex. Magnesium Carbonate

FeSO3

Iron (II) Sulfite

*Dot diagram- This uses the symbol of the element and dots to represent the valence electrons.  (Lewis Structure or electron dot.)

*Valence electrons=Electrons in the outermost energy level.

(Electrons from S and P shells.)

*Octet rule: This results when atoms gain or lose electrons to get eight electrons in their outer energy level.

*Duet rule: This results when atoms gain or lose electrons to get two electrons in their outer energy level.

 STOP HERE!

*NATURAL WATER PURIFICATION

   Raindrops and snowflakes are natures purest water form.

   Present day rain is less pure than before.

   Rain water dissolves organic materials.

WATER CYCLE (hydrologic Cycle)

1.Evaporation-(Liquid to gas)Pure water changes from a liquid to a gas.

2.Condensation-(Gas to liquid)Liquid forms around a particle in the air.

3.Bacterial Action-Microscopic organisms break down organic matter that is in the water.

4.Filtration-Large objects are removed from the water.

   In acid soils minerals are removed (calcium, magnesium, and iron(III) are picked up).

-REGENERATED- a process in which substances are removed from resin by being washed by excess salt water. (usually done at night)

-Salt is added Na+1 takes the place of Ca+2,Mg+2,Fe+3 and water sticks in Resin.

ION SYMBOL

ION NAME

ION SYMBOL

ION NAME

NH4+1

Ammonium

CO3-2

Carbonate

NO2-1

Nitrite

HCO3-1

Hydrogen Carbonate

NO3-1

Nitrate

ClO-1

Hypochlorite

SO3-2

Sulfite

ClO2-1

Chlorite

SO4-2

Sulfate

ClO3-1

Chlorate

HSO4-1

Hydrogen Sulfate

ClO4-1

Perchlorate

OH-1

Hydroxide

C2H3O2-1

Acetate

CN-1

Cyanide

MnO4-1

Permanganate

PO4-3

Phosphate

Cr2O7-2

Dichromate

HPO4-2

Hydrogen Phosphate

CrO4-2

Chromate

H2PO4-1

Dihydrogen Phosphate

O2-2

Peroxide