CCl 4 MgCl 2 Guess at the names for these two compounds Guess at the names for these two compounds Predict whether each is ionic or molecular compound Predict whether each is ionic or molecular compound Understanding the difference in bonding, explain what the formula means for each. Draw pictures to help. Understanding the difference in bonding, explain what the formula means for each. Draw pictures to help. Starter 1/4

Ch. 7: Chemical Formulas and Compounds 7.1 Chemical Names and Formulas

Chemical Formulas molecular compound molecular compound number of atoms of each element contained in a single molecule of the compound number of atoms of each element contained in a single molecule of the compound NO 2, CH 2 Cl 2, NO 2, CH 2 Cl 2,

Chemical Formulas ionic compound ionic compound represents one unit represents one unit simplest ratio of the compound’s anions and cations simplest ratio of the compound’s anions and cations MgO, Mg(OH) 2, NH 4 Br MgO, Mg(OH) 2, NH 4 Br

Monatomic Ions ions formed from a single atom ions formed from a single atom Not all representative elements easily form ions Not all representative elements easily form ions Some atoms form covalent bonds instead Some atoms form covalent bonds instead Others form ions without noble gas configurations Others form ions without noble gas configurations d and p-block metals d and p-block metals many form 2+ or 3+, some +1 or +4 many form 2+ or 3+, some +1 or +4 listed on back of periodic table listed on back of periodic table

Monatomic Ions type of ion can be determined by looking at the number of valence electrons in the neutral atom type of ion can be determined by looking at the number of valence electrons in the neutral atom atom is more stable with a full shell atom is more stable with a full shell zero valence zero valence eight valence eight valence determine which is easier for the atom to achieve determine which is easier for the atom to achieve

Monatomic Ions cation cation positive positive if the atom looses electrons if the atom looses electrons B Mg Mg Rb Rb Al Al Na Na anion anion negative if the atom gains electrons N F S O Br

Naming Monatomic Ions cations cations positive ion positive ion written first in formula written first in formula by element’s name by element’s name add a Roman Numeral if it can form more than 1 type of ion add a Roman Numeral if it can form more than 1 type of ion that is called the STOCK SYSTEM that is called the STOCK SYSTEM anions anions negative ion written second in formula by element’s root name + - ide ending

Practice: Monatomic Ions Identify the ion created by each atom and give the name for it: Identify the ion created by each atom and give the name for it: Ga Ga Se Se Ca Ca I N Li Li

Binary Ionic Compounds compounds made of two different ions compounds made of two different ions Crossing Over Crossing Over 1. write two ion types with correct charges 2. make the anion’s charge, the cation’s subscript 3. make the cation’s charge, the anion’s subscript 4. simplify the ratio if possible combine the names of the two ions combine the names of the two ions

Practice Naming Al and O Al and O Al 3+ O 2- Al 3+ O 2- Al 2 O 3 Al 2 O 3 aluminum oxide aluminum oxide Mg and Br Mg and Br Mg 2+ Br 1- Mg 2+ Br 1- MgBr 2 MgBr 2 magnesium bromide magnesium bromide Cu and Br Cu and Br Cu 2+ Br 1- CuBr 2 copper (II) bromide OR Cu 1+ Br 1- CuBr copper (I) bromide

Practice Writing Formulas iron (III) sulfide iron (III) sulfide Fe 3+ S 2- Fe 3+ S 2- Fe 2 S 3 Fe 2 S 3 cadmium oxide cadmium oxide Cd 2+ O 2- Cd 2+ O 2- Cd 2 O 2 Cd 2 O 2 CdO CdO potassium nitride potassium nitride K 1+ N 3- K 3 N tin (IV) sulfide tin (IV) sulfide Sn 4+ S 2- Sn 2 S 4 SnS 2

Cmpds with Polyatomic Ions the cation or anion could be a group of covalently bonded atoms instead of one atom the cation or anion could be a group of covalently bonded atoms instead of one atom most polyatomic ions are oxyanions: most polyatomic ions are oxyanions: polyatomic ions containing oxygen polyatomic ions containing oxygen more than one polyatomic anion can exist for one element more than one polyatomic anion can exist for one element sulfate ion: SO 4 2- sulfite ion: SO 3 2- sulfate ion: SO 4 2- sulfite ion: SO 3 2-

Practice Naming KNO 3 KNO 3 potassium nitrate potassium nitrate from K 1+ and NO 3 1- from K 1+ and NO 3 1- Cu(OH) 2 Cu(OH) 2 copper (II) hydroxide copper (II) hydroxide from Cu 2+ and OH 1- from Cu 2+ and OH 1- NH 4 Br NH 4 Br ammonium bromide from NH 4 1+ and Br 1- CaSO 4 CaSO 4 calcium sulfate from Ca 2+ and SO 4 2-

Practice Writing Formulas sodium permanganate sodium permanganate Na 1+ MnO 4 1- Na 1+ MnO 4 1- NaMnO 4 NaMnO 4 iron (II) chlorite iron (II) chlorite Fe 2+ ClO 2 1- Fe 2+ ClO 2 1- Fe(ClO 2 ) 2 Fe(ClO 2 ) 2 ammonium acetate ammonium acetate NH 4 1+ CH 3 COO 1- NH 4 CH 3 COO calcium carbonate calcium carbonate Ca 2+ CO 3 2- CaCO 3

Starter 1/6 Write the formula for Write the formula for barium nitrate barium nitrate zinc phosphate zinc phosphate

Traditional vs. Stock Stock System Stock System using Roman Numerals in names of metal ions with more than one charge using Roman Numerals in names of metal ions with more than one charge more important and used more often more important and used more often Traditional Traditional add –ic or –ous ending to metal name add –ic or –ous ending to metal name lower charge: -ous, higher charge: -ic lower charge: -ous, higher charge: -ic Shown on the chart below Stock System chart Shown on the chart below Stock System chart

Examples stannous chloride stannous chloride SnCl 2 SnCl 2 chromic sulfate chromic sulfate Cr 2 (SO 4 ) 3 Cr 2 (SO 4 ) 3 plumbic nitrate plumbic nitrate Pb(NO 3 ) 4 Pb(NO 3 ) 4 aurous oxide aurous oxide Au 2 O ferric phosphate ferric phosphate FePO 4 cuprous chlorate cuprous chlorate CuClO 3

Examples CuCl 2 CuCl 2 cupric chloride cupric chloride Pt 3 (PO 4 ) 2 Pt 3 (PO 4 ) 2 plantinous phosphate plantinous phosphate AuBr AuBr aurous bromide aurous bromide PbO PbO plumbous oxide SnO 2 SnO 2 stannic oxide Fe(NO 3 ) 2 Fe(NO 3 ) 2 ferric nitrate