-A double replacement is a reaction between two IONIC compounds usually in solution. The ions switch partners like a dance. The (+) ions sitch places but remember to watch your charges.
General Formula
AB + CD→ CB+AD
Eg: CaCO3 + 2HCl → CaCl2 + 2H2
The reactants change state during reaction
(usually a precipitate occurring)
Use your "Table of solubilities" to determine the states.- (aq) or (s)
Net Ionic Equation:
-There is a net reaction when you have a precipitation that occurs
-(aq) ions that are the same on both sides get cancelled
Eg.
CaCl2 + Na2CO3 → CaCO3 + 2 NaCl
Net Ionic Equation： 2Cl- + 2Na+ → 2NaCl
Using the Table of Solubilities
1) Find your anion ( negative ion) in the left hand column.
2) Look for your cation (positive ion) in the list in the 2nd column.
3) Follow its presence or absence to the word "soluble" or "not soluble"
4) If soluble, the compound is (aq)
5) If insoluble, the compound is (s)
-A combusion reaction is a reaction where burning in air is involved. The reactants are the chemical to be burned and the oxygen that it reats with. The oxygen atoms usually end up combined with more that one type of atom as products.
-General Formula
AB + O2 → AO + BO
Eg. CH4 + 2 O2 → 2 H2O + CO2
Neutralization
-A neutralization reaction is a sepcial double replacement reaction where acids reat with bases to produce water and an ionic salt as products.
-The acids have han H+ as the cation (+) and the bases have OH- as the anion (-). Both should be aqueous solutions. (aq)
HA + BOH → H2O + BA
Eg. HCl + NaOH → NaCl + H2O
NOTE： For DR reaction (include Neutralization）, some ions participate in the reaction wile other ions do not participate.
Eg. KCl(aq） + AgNO3(aq) → KNO3(aq) + AgCl(s)
* Be sure to write both the total and net ionic equations!!!
Total ionic equation: K+(aq) + Cl- (aq) + Ag+(aq) + NO3-(aq） → K+(aq) + NO3-(aq) + AgCl(s)
Net Equation: Ag+(aq) + Cl-(aq) → AgCl(s)
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