Chapter 20 Practice WS (Round 2)
Step 1: Identify if the items being bonded are metals or nonmetals.
Metals w/ nonmetals – ionic
Nonmetals w/nonmetals – covalent
Step 2: If it is ionic bonds, you will use the criss-cross method. You will have to balance oxidation
numbers.
Covalent bonds – use Greek prefixes and don’t worry about balancing oxidation numbers.
Step 3: Identify if any polyatomic ions are present - a good hint is if there are more than 2 elements
present, there will be at least one polyatomic ion in the bond. Also, polyatomic ions mean you will be
doing an ionic bond.
Step 4: Follow the rules from the cheat sheet.
Name the compound.
K2O – potassium oxide
Ca3N2 – calcium nitride
Sr(OH)2 – strontium hydroxide
K2CrO4 - potassium chromate
Na2SO4 – sodium sulfate
Na2SO3 – sodium sulfite
CuCl2 – copper I chloride
Br2F3 - dibromine trifluoride
(NH4)2O – ammonium oxide
H3OCl – hydronium chloride
Ba(C2H3O2)2  7H2O – barium acetate heptahydrate
NaCl – sodium chloride
Fe2O3 – iron (III) oxide
Write the chemical formula for the compound stated.
Magnesium cyanide – Mg(CN)2
Potassium chloride trihydrate – KCl * 3H2O
Beryllium nitrate - BeNO3
Beryllium nitrite - BeNO2
Copper (II) carbonate – CuCO3
Copper (I) carbonate – Cu2CO3
Carbon monoxide - CO
Carbon dioxide - CO2
Trisulfur heptachloride - S3Cl7
Monosulfur trioxide - SO3
Potassium phosphate - K3PO4
Magnesium phosphate – Mg3PO4
Aluminum phosphate – AlPO4
SPOILER WARNING _ CONTAINS ANSWERS!
Hide from yourself until you have completed them all!
K2O – potassium oxide
Magnesium cyanide – Mg(CN)2
Ca3N2 – Calcium nitride
Potassium chloride trihydrate – KCl  3H20
Sr(OH)2 – Strontium hydroxide
Beryllium nitrate – Be(NO3)2
K2CrO4 –Potassium chromate
Beryllium nitrite – Be(NO2)2
Na2SO4 – Sodium sulfate
Copper (II) carbonate – CuCO3
Na2SO3 – Sodium sulfite
Copper (I) carbonate – Cu2CO3
CuCl2 – Copper (II) chloride
Carbon monoxide - CO
Br2F3 – Dibromine trifluoride
Carbon dioxide – CO2
(NH4)2O – Ammonium oxide
Trisulfur heptachloride – S3Cl7
H3OCl – hydronium chloride
Monosulfur trioxide – SO3
Ba(C2H3O2)2  7H2O – Barium acetate
heptahydrate
Potassium phosphate – K3PO4
Magnesium phosphate – Mg3(PO4)2
NaCl – Sodium chloride
Aluminum phosphate – AlPO4
Fe2O3 – Iron (III) oxide
I hope you can forgive me if any of these are wrong. I made them all up in about 15 minutes. Good
luck!