1. Predicting Products

2. When Predicting Products
Write formulas for the reactants
Determine what kind of reaction it is
Write formulas for the products based on type of reaction
Balance the equation

3. Don’t forget diatomic elements!!!
H2, N2, O2, F2, Cl2, Br2, and I2
Elements that when found free in nature are 2 atoms bonded together
Will have other subscripts when in compounds but not when alone

4. Synthesis Usually the reactants will be single elements
Product is 1 compound made of the reactants
Use the rules we learned earlier for writing formulas
Sodium reacts with chlorine
Magnesium + oxygen

5. Decomposition Will have only 1 reactant
Products are smaller pieces of the original
Usually just the elements
See exceptions next 2 slides
Mercury oxide + heat
Water + electricity

6. Decomposition of Metal Carbonates
Any metal bonded with CO3
When heated makes metal oxide (metal bonded to O) and CO2
Calcium carbonate decomposes

7. Decomposition of Metal Hydroxides
Any metal bonded to OH
When heated makes metal oxide and H2O
Calcium hydroxide + heat

8. Combustion Reactants are organic compound and O2
Products are always CO2 and H2O
Propane + oxygen
Octane + oxygen

9. Single Displacement Reactants are free element and a compound
In products free element replaces the ion most like it in the compound
Must refer to the activity series
Aluminum + zinc II chloride
Magnesium + hydrochloric acid

11. Single Displacement cont’d
iron + potassium chloride
Sodium nitride + oxygen

12. Double Displacement Reactants are usually 2 ionic compounds
Products are 2 ionic compounds where the cations have traded places
Potassium fluoride + calcium bromide
Hydrochloric acid + sodium hydroxide