Types of chemical reactions Part II

Types of REactions Synthesis Reactions Decomposition Reactions Single Displacement Reactions Double Displacement Reactions Combustion Corrosion

Single displacement Reactions General pattern for reaction: AB + C → AC + B The “Home-wrecker”

single displacement reaction Investigation Copper wire in silver nitrate Cu (s) + Ag(NO 3 ) 2 (aq) → ?? Predict what will happen when a piece of copper wire is added to a silver nitrate solution. I think that... because...

Safety TIME! Goggles and Lab Aprons Required beyond this point!!!

Cu (s) + Ag(NO 3 ) 2 (aq) → ?? In groups of 3: Collect 1 piece of copper wire A beaker with 100 ml silver nitrate solution Make observations about the reactants

Cu (s) + Ag(NO 3 ) 2 (aq) → ?? All together as a class: Each group: add the piece of copper wire into silver nitrate solution Record observations Check out page 240 in text for more! Conclusion: What are the products of this reaction?

Rules for single displacement reactions Involve an ionic compound - always the positive ion (cation) that is replaced Eg. 2Mg (s) + CO 2 (g) →2MgO (s) + C (s) Often occur in aqueous solution: Eg. Cu (s) + 2Ag(NO 3 ) 2 (aq) → Cu(NO 3 ) 2 (aq) + 2Ag (s)

Rules for single displacement reactions Also occur when metals are placed in acid Chemical formula of acid includes 1 or more H’s Metals displace H atoms Eg. Zn (s) + 2HCl (aq) → H 2 (g) + ZnCl 2 (aq)

double displacement reactions Reaction occurs when 2 elements in different compounds trade places General pattern: AB + CD → AD + CB The “Swingers”

Double Displacement Reaction Investigation Sodium thiocyanate + Iron (III) nitrate → ??? NaSCN (aq) + Fe(NO 3 ) 3 (aq) → ??? Predict what will happen when these 2 solutions are mixed. I think that.... because...

NaSCN (aq) + Fe(NO 3 ) 3 (aq) → ??? In your group of 3 Collect: 1 Erlenmeyer flask 2 test tubes: 1 Half full of Fe(NO 3 ) 3 (aq) 1 Half full of NaSCN (aq) Make observations about the reactants

NaSCN (aq) + Fe(NO 3 ) 3 (aq) → ??? At the same time as a class: Add contents of test tubes into flask Record Observations Conclusions: What are the products of this reaction??

Double Displacement Reactions Many reactions occur between 2 ionic compounds in solution: Eg. lead (III) nitrate + potassium iodide → lead (III) iodide + potassium nitrate Pb(NO 3 ) 2 (aq) + 2KI (aq) → PbI 2 (s) + 2K(NO 3 ) 2 (aq) Some ionic compounds do not dissolve in water, they become visible as precipitate Precipitate: solid formed in solution

Homework Page 243 # 2, 4, 5 and 7