Chapter 8 Chemical Equations Review Sheet
1.
Combination Reactions – when two or more substances combine to make ONE product
A + B  C
I.
II.
Metals + Oxygen  Metal oxide
Nonmetal + Oxygen  Non-metal oxide
You can NOT predict the formula of the non-metal oxide because it depends on temperature and pressure – Thus you must be given the NAME of the product
Ex – “Phosphorous and Oxygen gas react to form solid diphosphorus pentaoxide”
P + O
2
 P
2
O
5
BUT you must balance the equation!!
III.
Metal + Nonmetal = Binary Ionic Compound = rules from Ch. 7!
2.
Decomposition Reactions – ONE compound is broken down into 2 or more products AZ  A + Z
I.
Metal Hydrogen Carbonates (Metal + HCO
3
) – metal carbonates decompose when they are heated – this yields a metal carbonate, water, and carbon dioxide:
Metal hydrogen carbonate  (heat) Metal carbonate + water + carbon dioxide
NaHCO
3
 (heat) Na
2
CO
3
+ H
2
O + CO
2
** Balance the Eq**
Note the charge of the metal ion does NOT change – so you can predict the formula of the
II.
III.
metal carbonate!!! (Na stays +1 charge so sodium carbonate is Na
2
CO
3
)
Metal Carbonates (metal + CO
3
) – metal carbonate decomposes into metal oxide plus carbon dioxide gas
Metal carbonate  (heat) Metal oxide + carbon dioxide
CaCO
3
 (heat) CaO + CO2 ** Balance the Eq**
Miscellaneous Oxygen Containing Compounds  A compound containing oxygen decomposes to release oxygen gas. There is NO way of predicting these thus the names
MUST be given!

3.
Single Replacement Reactions A +BZ  AZ + B
IF “A” is more active than “B” – then it will replace “B” in the compound
IF “A” is less active than “B” – there will be NO REACTION (NR)
***Look at Activity Series to determine if A is more active than B***
Activity Series for Metals Li  K  Ba  Sr  Ca  Na  Mg  Al  Mn  Zn  Fe  Cd  Co  Ni  Sn  Pb  H
 Cu  Ag  Hg  Au
Metals that procede (H) react with acids and those after (H) do NOT react with acids (Cu/Ag/Hg/Au)
Active Metals – a few metals are so reactive that they react directly with water at room temp
(Li/K/Ba/Sr/Ca/Na)
I.
II.
Metal 1 + Aq solution 1  metal 2 and Aq solution 2
Metal + Aq acid  Aq solution + Hydrogen gas (Only if the metal reacts with acids!!)
III.
Metal + water  metal hydroxide + hydrogen gas (Only if the metal is an active metal!!)
4.
Double Replacement Reactions AX + BZ  AZ + BX = “Precipitation Reactions”
Aq solution 1 + Aq solution 2  precipitate + aq solution 3
You MUST use the SOLUBILITY rules to determine which product is the precipitate.
IF all of the products are soluble then there is NO PRECIPITATE which means there is NO REACTION!!!
5.
Neutralization Reactions – Acid + Base  Salt + Water
- Use the ions from the acid and the base to form the salt and water