Predicting Reaction Products Chapter 9 Predicting Reaction Products

1. Single Replacement Reactions Single Replacement Reactions occur when one element replaces another in a compound. A metal can replace a metal (+) OR a nonmetal can replace a nonmetal (-). element + compound compound + element A + BC  AC + B (if A is a metal) OR A + BC  BA + C (if A is a nonmetal) (remember the cation always goes first!) When H2O splits into ions, it splits into H+ and OH- (not H+ and O2- !!)

Single Replacement Reactions Predict the products of the following reaction: Aluminum metal reacts with aqueous hydrochloric acid (HCl). Al(s) + HCl(aq)  Al(s) + HCl(aq)  AlCl3(aq) + H2(g)

Practice Al + Sn3P2 → Cr(NO3)3 + Pb → F2 + Na2O → Na + water →

2. Double Replacement Reactions Double Replacement Reactions occur when the cations in two compounds switch places. compound + compound  compound + compound AB + CD  AD + CB

Double Replacement Reactions To build your two new compounds switch the cations. Check ion charges to build neutral compounds and write the cation first. Example: AgNO3(aq) + NaCl(s)  Another example: K2SO4(aq) + Ba(NO3)2(aq)  AgCl(s) + NaNO3(aq) KNO3(aq)+ BaSO4(s)

Practice HCl + AgNO3  CaCl2 + Na3PO4  Pb(NO3)2 + BaCl2  FeCl3 + NaOH 

3. Decomposition Reactions The simplest decomposition reactions occur when a binary compound breaks up into its elements. Compound  Element + Element In general: AB  A + B Example: 2 H2O  2H2 + O2 Example: 2 HgO  2Hg + O2

Decomposition PbO2(s)  AlN(s) 

Practice Mg3P2 → LiCl →

4. Synthesis reactions The simplest Synthesis reactions occur when two elements combine and form a binary compound. element + element  compound Basically: A + B  AB Example: 2H2 + O2  2H2O Example: Fe + Cl2  FeCl2

Synthesis Na(s) + Cl2(g) 

Practice Mg(s) + F2(g)  Al(s) + O2(g) 

Combustion Combustion reactions combine a hydrocarbon with oxygen to produce carbon dioxide and water. C5H12 + O2  CO2 + H2O

Practice C10H22 + O2  C12H22O11 + O2 

Predicting the Products of Reactions – In Class Examples (In Notebook) HgO  Hg + O2 Al + Pb(NO3)2  Pb + Al(NO3)3 K + water  H2 + KOH N2O5  N2 + O2 PbCl2 + Li2SO4  LiCl + PbSO4

Predicting the Products of Reactions – In Class Examples Cl2 + LiI  LiCl + I2 H2 + O2  H2O AgNO3 + K2SO4  KNO3 + Ag2SO4 CH3OH + O2  CO2 + H2O Pb + Cu(NO3)2  Cu + Pb(NO3)2 or Pb(NO3)4

Predicting the Products of Reactions – In Class Examples C3H8 + O2  CO2 + H2O MgBr2 + FePO4  Mg3(PO4)2 + FeBr3 Li2S  Li + S K + Br2  KBr

Homework “6 example problems” (on the back of Prediction of Reaction Products – In Class Examples).