Turning chemistry into algebra Ionic Formulas Turning chemistry into algebra

REVIEW We can tell how many electrons an atom will gain or lose by looking at its valence electrons. Metals like to lose electrons. (Cations) Ex. Na + Nonmetals like to gain electrons. (Anions) Ex: O 2- All elements try to have a full valence of 8 electrons(OCTET RULE).

Chemical Bonding A chemical bond is the force of attraction that holds two atoms together. Cl Na Attractive Force

Why do elements form chemical bonds? Atoms form chemical bonds in order to fill their outermost energy level with electrons. A full valence causes an atom to be more stable. A full valence consists of 8 valence electrons.

Ionic Bonding Ionic bonds: Transfer of electrons from one atom to another, producing oppositely charged ions which attract each other. (usually transfer from metal to nonmetal) Na + + Cl-  NaCl

How do we figure out what can bond with what? 1. Make sure to have cation + anion 2. Balance the charges. Na+ F− (1+) + (1-) = 0 1 Na+ and 1 F− = NaF NaF is the correct chemical formula for these two elements

Write an ionic formula for K+ bonding with S2− Balance the charges. K+ S2− K+ 2(1+) + (2-) = 0 2 K+ and 1 S2− = K2S

Write an ionic formula for Fe3+ bonding with OH− Balance the charges. Fe3+ OH− OH− (3+) + 3(1-) = 0 1 Fe3+ and 3 OH− = Fe(OH)3

Al2S3 Al3+ and S2- an ionic compound composed of: Write the formula for… an ionic compound composed of: Al3+ and S2- Al2S3

Cd(NO2)2 Cd2+ and NO2- an ionic compound composed of: Write the formula for… an ionic compound composed of: Cd2+ and NO2- Cd(NO2)2

Ag2CO3 Ag+ and CO32- an ionic compound composed of: Write the formula for… an ionic compound composed of: Ag+ and CO32- Ag2CO3

Pb(NO3)2 Pb2+ and NO3- an ionic compound composed of: Write the formula for… an ionic compound composed of: Pb2+ and NO3- Pb(NO3)2

Hg3(PO4)2 Hg2+ and PO43- an ionic compound composed of: Write the formula for… an ionic compound composed of: Hg2+ and PO43- Hg3(PO4)2

Naming Ions and ionic formulas

Naming Cations Cation- if the charge is always the same (Group A) just write the name of the metal. Transition metals can have more than one charge, so indicate the charge with roman numerals in parentheses.

Naming Cations Name the following: Na+ Fe+2 Fe+3 Pb+2 iron (II) sodium iron (II) iron (III) lead (II)

Naming Cations Write formulas for the following: Potassium ion K+ Copper (II) ion Cu2+ Barium ion Ba2+ Mercury (II) ion Hg2+

Naming Anions Anions are always the same, change the element ending to – ide F-1 Fluorine

Naming Anions Anions are always the same, change the element ending to – ide F-1 Fluoride

Naming Anions Name the following: Cl- N-3 Br- O-2 chloride nitride bromide oxide

Naming Anions Write formulas for the following: sulfide ion S2- iodide ion I- phosphide ion P3- fluoride ion F-

Naming Ionic Compounds Cation + Anion. To write the names just name the two ions. NaCl = Na+ Cl- = sodium chloride MgBr2 = Mg+2 Br- = magnesium bromide

Naming Ionic Compounds Write the name of CuO Need the charge of Cu, O is -2 copper must be +2 Copper (II) oxide

Naming Ionic Compounds Write the names of the following KCl potassium chloride Na3N sodium nitride PbO lead (II) oxide PbO2 lead (IV) oxide