Chemical Formulas and Chemical Compounds

Chemical Formulas and Chemical Compounds 7.1

Naming Binary Ionic Compounds • Binary Ionic Compound (BIC) -ionic compound made up of two ions • To name cation – use name of atom • Na+ = sodium K+ = potassium • Ca2+ = calcium Ba2+ = barium

Naming Anions • To name anions, use the atom’s base name and –ide at the end • Cl- = Chloride S2- = Sulfide • P3- = Phosphide O2- = Oxide • KBr = Potassium bromide • Mg3N2 = Magnesium nitride

Naming • FrF • SrBr2 • Li2Se

Writing Ionic Formulas • Write the symbol and charge of each ion side by side (cation first) • If total = 0, just write symbols & you are done! • If total does not = 0, criss cross charges to have overall 0 charge

Formula Writing Practice • Magnesium sulfide • Rubidium Oxide • Strontium Bromide • Aluminum Oxide

Multiple Charge Cations/Transitions & Group 14 • If cation has multiple charges, use a roman numeral to indicate charge • Cu+ =Copper (I) Cu+2 =Copper (II) • I = 1 II = 2 III = 3 IV = 4 • V = 5 VI= 6 VII = 7 VIII = 8 • IX = 9 X = 10

Determining Charge on Transition Metals • The charge on ionic compounds has to be electrically neutral • Figure out overall charge on anion and then determine what charge cation has to be • CuCl2 ~Each Cl has a charge of -1 (needs 1 e-) and since there are 2 of them, the overall charge of Cl is -2. Cu must be +2 = Copper (II) chloride

Determining Charge on Transition Metals • PbO2 Charge on O is -2 and there are 2 of them so overall on O is -4. • Pb has to be +4 • Lead (IV) oxide

Practice • CuO • Hg2O • Cu2O • Vanadium (III) Iodide • Platinum (IV) oxide

Polyatomic Ions • Polyatomic Ion – an ion made of 2 or more atoms that behave like a single ion • Bonded covalently • Bond ionically with other simple ions as salts

Naming Compounds w/polyatomics • Name the ion that is not a polyatomic like simple cations or anions and then name the polyatomic as the chart says • NaOH = Sodium hydroxide • CaCO3 = Calcium carbonate

Polyatomic Ions • AlPO3 • LiSCN • FeSO4 • Mn(Cr2O7)2

Formula Writing w/polyatomics • Determine charge of overall polyatomic and then the other ion. • Follow same rules as before. • Beryllium cyanide • Copper (II) nitrate

Polyatomic Ions • Barium sulfide • Potassium oxalate • Chromium (III) cyanide • Vanadium (V)silicate

Oxyanions • Name changes as number of O changes • Gain 1 O = perchlorate ClO4- • Base Name = chlorate ClO3- • Lose 1 O = chlorite ClO2- • Lose 2 O = hypochlorite ClO-

Hydrogen and Sulfur • The name usually starts with the word hydrogen, but use mono- and di- • HPO4 –monohydrogen phosphate • H2PO4 – dihydrogen phosphate • Thio – replace O with S • K2S2O3 – Potassium thiosulfate

Naming Covalent Compounds • Inorganic molecular compounds • Specify # of each type of atom • P4O6 – Tetraphosphorus hexoxide • P4O10 – Tetraphosphorus decoxide

Cova l en t p r e f ixes

Naming Covalent Compounds • If there is 1 of the first element, mono is omitted from the word • CO – carbon monoxide • CO2 – carbon dioxide

Naming Covalent Compounds • 1st element – named 1st – usually least e-neg • 2nd element – named 2nd – usually most e-neg – add ide ending • Drop vowels o and a from prefix before adding it to a root that starts with a vowel

Naming Covalent Compounds • N2O4 – Dinitrogen tetroxide • SF6 – Sulfur hexafluoride • Some common names are used instead of technical name • H2O – water – not dihydrogen monoxide

Chemical Formulas and Chemical Compounds