SCIENCE - 4TH

Chemical Bond

The force that holds molecules or compounds together.

Valence electrons

Electrons in the outermost shell of an atom.

Metals

hold onto their electrons very tightly

Nonmetals

have very loose and free-flowing electrons.

Electronegativity

ability of an atom to attract electrons to itself

Ionic Bond

complete transfer of electrons from a metal to nonmetal.-

Covalent Bond

occurs between nonmetals, sharing of electrons.

Nonpolar Covalent Bond

formed when two identical non-metallic atoms

Polar Covalent Bond

formed when two different non-metallic atoms

Ions

a changed atom or molecule

• they form when an atom loses or gains electrons

Ionic Compound

formed when a metal atom transfers its valence electrons to a nonmetal atom.

Monoatomic ion

atoms that either gain or lose electrons.

Polyatomic ion

a group of atoms that acts as one, and carries a charge.

Binary

ionic compounds composed of only two elements.

• NaCl (Sodium Chloride)

Ternary

ionic compounds composed of three or more elements.

• CaCo3 (Calcium Carbonate)

Naming Binary Ionic Compounds

metal name, nonmetal + ide

• Mg3N2 - Magnesium Nitride

Binary Ionic Compound, Stock System

Metal name (Roman numeral), Nonmetal + ide

• FeCl2 - Iron (||) Chloride

Binary Ionic Compound, Classical System

(Latin name + ous/ic) + Nonmetal name +ide)

• FeCl2 - Ferrous Chloride

• FeCl3 - Ferric Chloride

Naming Ternary Ionic Compounds

metal name + polyatomic ion name

• Na3PO4 - Sodium Phosphate

• Ca(OH)2 - Calcium Hydroxide

Naming Ternary Ionic Compounds, Stock system

Metal name (Roman numeral) + polyatomic ion name

• Fe2(SO4)3 - Iron (|||) Sulfate

Naming Ternary Ionic Compounds, Classical system

latin name + ous/ic + polyatomic ion name

• Fe2(SO4)3 - Ferric Sulfate

Molecular compound

occurs between nonmetallic atoms sharing their valence electron

Naming of Binary Molecular Compound

first element with prefix (do not put mono) + second element with prefix & ide

• N2O4 - Dinitrogen Tetroxide

• CO - Carbon Monoxide

Binary acid

-an acid that contains of hydrogen and one other element.

-hydro + element + - acid

• HBr - Hydrobromic acid

Ternary acid

-an acid that consists of two elements, usually hydrogen and a polyatomic ion

-ite = ous acid

-ate = ic acid

• - Hydrogen + nitrite = Nitrous acid

Molecular Mass

mass of one molecule of a covalent compound (nonmetal + nonmetal)

Formula Mass

mass of one molecule of an ionic compound. (metal + nonmetal)

How do you get the Formula Mass/ Molecular Mass?

1 - Find their atomic mass = Get their atom number x atomic weight

2 - Add the atomic mass

3 - added atomic mass / 6.02

4 - You’ll get the Formula mass = ___ x 10 (23) g/formula unit OR g/molecule

How do you get the Percent Composition?

1 - Find the elements mass = Get their atom number x Atomic weight =

2 - Add all of the elements mass

3 - Find their % mass = mass of N / Added elements mass

4 - To make sure their correct, they all have to add up to 100%

How to find the Empirical Formula?

Note: There are already given, the elements % and the molar mass.

1 - Given element % / Atomic weight

2 - Divide by the smallest number

3 - Times them to be a whole number

4 - Then you’ll have the Empirical Formula

5 - Molar mass / Empirical mass ( whole number x atomic weight, then add)

6 - Molecular Formula