Alberta Science 10-Chemistry-Section 2.2

Polyatomic Molecular Elements

(poly=many) Non-metal in groups of more than two. There are only three. Phosphorous and Sulfur P4, S8, O3

Ionic Compounds

-made of metallic and non-metallic ions -electrostatic charge holds them together when they exchange electrons - no net charge -form crystal lattice

Molecular Compounds

-made of two non-metals -SHARE ELECTRONS (not exchange) (covalent bonds) -no ions -attraction of electrons to other nucleus holds together atoms - poor conductors; dissolve poorly in water

Multivalent Ionic Compound

-metal ion with more than one charge (charge must be specified) and non-metal ion -usually transition metals

Polyatomic Ions (Naming)

-names and formulas for these MUST BE LOOKED UP because they don't follow any rules. -cations before anions. -keep the same ending because they already have "ite" "ate" or "ide" ending. -when there is more than polyatomic ion USE BRACKETS to show that there is more that one polyatomic ion. "-ate" means more oxygen "-ite" means fewer oxygen Calcium Phosphate Ca (2+) PO4 (3-) Ca3(PO4)2

Molecular Coumpounds (naming)

-prefix for first element (unless there is only one) -prefix and "ide" ending for second element Prefixes mono-one di-two tri-three tetra-four penta-five hexa-six hepta-seven octa-eight nona-nine deca-ten

Multivalent Compounds (naming)

Metal then non-metal with "ide" ending Iron (II) + Bromine Fe (+2) + Br(-1) FeBr2 (s)

Ionic Compounds (Naming)

Name cation (usually metal) is always listed first, then non-metal with "ide" ending. Mg (+2) + Cl (-1) MgCl2 (s)

Diatomic Molecular Elements

Non-metals that always show up in groups of two. Share valence electrons with itself. remember "-gens" H2, N2,O2, and halogens

Molecular compounds that need to be known

Water-H20 (l) Ammonia-NH3 (g) Ozone-O3 (g) Methane-CH4 (g) Ethane-C2H6 (g) Sucrose-C12H22O11 (s) Glucose-C6H12O6 (s) Hydrogen Peroxide-H2O2 (l) Methanol-CH3OH (l) Ethanol-C2H5OH (l) Propane - C3H8

Multivalent Elements

an element with more than one stable ion . Roman numerals are used when writing their names.

Polyatomic Ions

composed of one or more nonmetal elements. They will show a charge in their formula

Covalent Bond

formed when atoms share electrons

Molecule

forms when two or more non-metallic atoms bond together.