 Synthesis – 1 product  Decomposition – 1 reactant  Single displacement – 1 element & 1 compound react to produce a different element & a different compound  Double displacement – 2 compounds react to form two different compounds.  Neutralization – acid and base in the reactants & water as one of the products.  Combustion – O 2 as a reactant & CO 2 and H 2 O as the products.

 Does your reaction have two (or more) substances combining to form one compound? If yes, then it's a synthesis reaction.  2 H 2(g) + O 2(g)  2 H 2 O (l)  Na (s) + Cl 2(g)  NaCl (s)

 Does your reaction have one compound breaking down to make two or more smaller substances? If yes, then it's a decomposition reaction.  2 HgO (l)  2 Hg (l) + O 2(g)  NaHCO 3(s)  Na 2 CO 3(s) + H 2 O (l) + CO 2(g)

 Does your reaction start with a compound and an element and produce a different compound and a different element? If yes, then it's a single displacement reaction.  CuCl 2(aq) + Mg (s)  MgCl 2(aq) + Cu (s)  KCl (aq) + F 2(g)  KF (aq) + Cl 2(g)

 A double displacement reaction starts with two compounds and makes two new compounds.  FeCl 3(aq) +MgSO 4(aq)  Fe 2 (SO 4 ) 3(s) +MgCl 2(aq)  NaCl (aq) + AgNO 3(aq)  NaNO 3(aq) + AgCl (s)

 Does your reaction have an acid as one of your reactants and water as one of the products? If yes, then it's an acid-base or neutralization reaction.  HCl (aq) + NaOH (aq)  NaCl (aq) + H 2 O (l) acid base  Ca(OH) 2(aq) + H 3 PO 4(aq)  H 2 O (l) + Ca 3 (PO 4 ) 2(aq) base acid

 Does your reaction have oxygen as one of it's reactants and carbon dioxide and water as products? If yes, then it's a combustion reaction.  CH 4(g) + O 2(g)  CO 2(g) + H 2 O (g)  C 8 H 18(g) + O 2(g)  CO 2(g) + H 2 O (g)

 To predict the products for any equation, you must first determine the type of reaction by looking at the reactants.  Synthesis – 1 product  Decomposition – 1 reactant  Combustion – O 2 as a reactant & CO 2 and H 2 O as the products.

 2 or more reactants and you’re told that there’s only one product = synthesis  When writing the products, you must look at the charges of the ions. The equations will most likely not be balanced!  Example: Al (s) + Br 2(l)   Example: Ca (s) + N 2(g) 

 1 reactant = decomposition (if you have a decomposition, then it will be a compound splitting up into its elements)  Remember the “7” diatomic molecules and to write them with a “ 2 ” if by themselves.  Example: CCl 4(l)   Example: Mg 3 N 2(s) 

 hydrocarbon (compound with C & H) + O 2 = combustion (always have CO 2 and H 2 O as your products)  Example: CH 4(g) + O 2(g)   Example: C 3 H 8 O (g) + O 2(g) 

 C 8 H 18 + O 2   Ba(NO 3 ) 2   Mg + O 2 

 Single displacement – 1 element & 1 compound react to produce a different element & a different compound  Double displacement – 2 compounds react to form two different compounds.  Neutralization – acid and base in the reactants & water as one of the products.

 1 element & 1 compound = single displacement (replacement)  In the products, you can’t have two positive ions or two negative ions combined together, only one positive and one negative ion.  Example: Mg (s) + Zn(NO 3 ) 2(aq)   Example: Cl 2(g) + KF (aq) 

 2 ionic compounds = double displacement (replacement). As before, you can’t put two positive ions or two negative ions together.  Example: AgNO 3(aq) + NaCl (aq)   Example: Fe 2 (SO 4 ) 3(aq) + Na 3 PO 4 (aq) 

 1 acid (starts with H) & 1 base (ends with OH) = acid-base or neutralization (always makes H 2 O as one product)  Water gets rid of all hydrogen and hydroxide ions. The other compound comes from the leftover ions.  Example: HCl (aq) + KOH (aq)   Example: Ca(OH) 2(aq) + H 2 SO 4(aq) 

 If a substance is an aqueous solution (aq), it is a substance that dissolves in water, or is soluble in water.  If a substance is insoluble, it will not dissolve in water, and when formed as the result of a reaction will appear as a precipitate (solid).  If a substance is slightly soluble or partially soluble in water, only a small portion of that substance will dissolve in water.

 Electrolyte – solution that that has the ability to conduct electricity.  When an ionic compound dissolves in water it separates into ions and is called a strong electrolyte, for example NaCl dissolved in water.  Compounds that dissolve in water but do not conduct electricity are called nonelectrolytes, for example, sugar dissolving in water.

 In order for a compound to be an aqueous solution, one of the ions (either the positive ion or the negative ion) must be soluble in water, but not both  FeCO 3  Ca(NO 3 ) 2  CuOH  CaCl 2  (NH 4 ) 2 SO 4  Zn 3 (PO 4 ) 2  SrO

 In all precipitation reactions, the ions of one substance are exchanged with the ions of another substance when their aqueous solutions are mixed  At least one of the products formed is insoluble in water KI(aq) + AgNO 3 (aq)  KNO 3 (aq) + AgI  s  K+K+ I-I- Ag + NO 3 - K+K+ Ag I

Here is what we’ve already covered  Determine what ions each aqueous reactant has  Exchange Ions ◦ (+) ion from one reactant with (-) ion from other  Balance Charges of combined ions to get formula of each product

° Determine Solubility of Each Product in Water ◦ solubility rules/table ◦ if any of the products are insoluble or slightly soluble, a precipitate will form ◦ If all substances formed are aqueous solutions then no precipitate will form and there is really no reaction, just ions floating around in water.

 Predict the products given each of the following reactants. Also denote which compound forms a precipitate: Cu(NO 3 ) 2(aq) + KOH (aq)  FeCl 3(aq) + Mg 3 (PO 4 ) 2(aq)  NaBr (aq) + KNO 3(aq) 

 Equations which describe the chemicals in aqueous solution and their product molecules are called molecular equations KCl(aq) + AgNO 3 (aq)  KNO 3 (aq) + AgCl(s)  equations which describe the actual ions and molecules in the solutions as well as the molecules of solid, liquid and gas not dissolved are called ionic equations  K + (aq) +Cl - (aq) +Ag + (aq) +NO 3 - (aq)  K + (aq) +NO 3 - (aq) +AgCl (s)

 ions that are both reactants and products are called spectator ions K + (aq) +Cl - (aq) +Ag + (aq) +NO 3 - (aq)  K + (aq) + NO 3 - (aq) + AgCl (s)  an ionic equation in which the spectator ions are dropped is called a net ionic equation Cl - (aq) + Ag + (aq)  AgCl (s)

 Write the molecular, complete ionic and net ionic equations for the following equations. Also identify any spectator ions : Cu(NO 3 ) 2(aq) + KOH (aq)  KNO 3(aq) + Cu(OH) 2(s)

 Write the molecular, complete ionic and net ionic equations for the following equations. Also identify any spectator ions : Fe 2 (SO 4 ) 3(aq) +Pb(ClO 3 ) 2(aq)  Fe(ClO 3 ) 3(aq) +PbSO 4(s)

 Write the molecular, complete ionic and net ionic equations for the following equations. Also identify any spectator ions : KCl (aq) + (NH 4 ) 2 SO 4(aq)  K 2 SO 4(aq) + NH 4 Cl (aq)