Chemical formula and equations

**Single Replacement Reactions
an element is substituted into a compound for another element in the compound:
A + BY => AY + B
Example: the reduction of metal oxides with carbon

**Double Replacement Reactions
two compounds exchange atoms or groups of atoms to produce two different compounds:
AX + BY => AY + BX

Example: the reaction of a metal carbonate with an acid
Precipitation
two soluble ionic compounds form an insoluble product, a precipitate, when mixed based

on

AX (aq) + BY (aq) => AY (s) + BX (aq)

AX (s) + H2O (l) => A+ (aq) + X- (aq)

BY (s) + H2O (l) => B+ (aq) + Y- (aq)