Notes 13 – Predicting Products of Chemical Reactions Sci 10Chemistry

How to Predict Products 1.Look at the reactants and identify the type of reaction  Synthesis if reactants are 2 small molecules or elements  Decomposition if reactants are 1 compound  Single displacement if reactants are 1 compound and 1 element  Double displacement if reactants are 2 compounds  Combustion if reactants are a molecule that contains C and H, with oxygen added (or if you see the words “burn” or “combust”)

2.Write the formulae for the products  Synthesis: Write a compound  Decomposition: Write 2 small molecules or elements  Single Displacement: Write a compound with a different cation or anion + the leftover element that got booted out  Double Displacement: Write 2 different compounds showing the double switch up  Combustion: Write carbon dioxide + water

3.Check formulae to ensure they are written correctly  i.e. ionic compounds have appropriate subscripts so total charge is zero  i.e. HOFBrINCl’s are written as pairs  i.e. molecular compounds have the proper subscripts 4.Balance the equation

Example 1.Methane is combusted  Must be combustion reaction (key word) CH 4 + O 2  CO 2 + H 2 O  Balance CH 4 + 2O 2  CO 2 + 2H 2 O

Example 1.Magnesium + sulfur  2 elements so must be synthesis Mg + S  MgS (Mg 2+, S 2-, charges = 0)  Balance Already balanced Already balanced

Example 1.Copper (III) oxide  1 Compound so must be decomposition Cu 2 O 3  Cu + O 2  Balance 2Cu 2 O 3  4Cu + 3O 2 HOFBrINCl !!!!!

Example 1.Magnesium + zinc nitrate  Element + compound so must be single displacement Mg + Zn(NO 3 ) 2  Mg(NO 3 ) 2 + Zn  Balance Already balanced Already balanced

Example 1.Sodium sulfate + barium chloride  2 compounds so must be double displacement Na 2 SO 4 + BaCl 2  NaCl + BaSO 4  Balance Na 2 SO 4 + BaCl 2  2NaCl + BaSO 4

Try It!  Predict the products of the following reactions: 1.Iron (III) + copper (I) nitrate  SD: Fe + 3CuNO 3  Fe(NO 3 ) 3 + 3Cu 2.Hexane (C 6 H 14 ) is completely combusted C: 2C 6 H O 2  12CO H 2 O 3.Ammonium nitrate + barium hydroxide  DD: NH 4 NO 3 + Ba(OH) 2  2NH 4 OH + Ba(NO 3 ) 2 4.Aluminum chloride  D: 2AlCl 3  2Al + 3Cl 2

To Do  Notes 13 Practice 1