1. Types of Chemical Reactions Chapter 11 Section 2

2. Objectives:  SWBAT:  Identify the type of reaction (synthesis/combination, decomposition, single replacement, double replacement, or combustion) by looking at the general patterns of these equations  You will accomplish this through completing today’s POGIL activity and actively participating when it is time for group discussion.

3. How will this POGIL activity work?  You will be in your groups  You will see a stop sign which means to stop  I will time each part so you know how much time you have to finish up the section  I will roll a dice to determine which group AND which person in the group will answer the key idea questions and possibly other questions.

4. Why classify chemical equations?  Let’s check out what our POGIL says!

5. Combination Reactions (Synthesis)  Two or more reactants come together to form one product  Keep an eye out for…  Two or more reactants  One product  A + B  AB  Example: 2Mg (s) + O 2 (g)  2MgO (s) +

6. Like the start of a dance…  Synthesis (Combination) is like when two people come together to start a dance…

7. Decomposition Reactions  A single compound breaks down into two or more simpler products  Keep an eye out for:  One reactant  Two products  Require some form of energy to break the initial compound  XY X+ Y  Example: 2HgO (s) 2Hg (l) + O 2 (g) + heat

8. Like the end of a dance…  Decomposition is like when two people are done dancing and step apart from one another.

9. Single Replacement Reactions  One element replaces a second element in a compound  Keep an eye out for  Products and reactants consisting of one element and one compound  Switch of one element for another in a compound  C + DE  CE + D  Example: Zn (s) + Cu(NO 3 ) 2 (aq)  Cu (s) + Zn(NO 3 ) 2 (aq) + +

10. Like when someone cuts in…  Single replacement is when one ion taps the shoulder of the other ion to cut into the dance…

11. Activity Series  Lists metals in order of reactivity  If a metal is more reactive (i.e., higher up on the activity series) it will replace another metal  Allows us to predict our products!  More on this later…

12. Halogens  A halogen can replace a halogen  The activity decreases top to bottom down group 7A  Thus, if one halogen is above another halogen, it can replace the halogen below it but none above it.  As with the Activity Series…more on this later when we get to predicting products!

13. Double-Replacement Reactions  Chemical change involving an exchange of positive ions between two compounds  Generally take place in aqueous solutions  Can only occur if…  One of the product is only slightly soluble and forms a ppt  One product is a gas  One product is a molecular compound  Keep an eye out for...  The above products  Switching of two cations  AB + XY  XB + AY  Example: Na 2 S (aq) + Cd(NO 3 ) 2 (aq)  CdS (s) + 2NaNO 3

14. People Switch Partners!  Double replacement is like when two dance partners switch.

15. Combustion Reactions  Reaction of a carbon-based compound with oxygen that produces carbon dioxide and water vapor  Used to produce energy  Like in power plants  Keep an eye out for:  Production of CO 2 (g) and H 2 O (g)  Reaction with O 2 (g)  C 2 H 2 (g)+ O 2 (g)  CO 2 (g) + H 2 O (g)

16. Last Question S DR D SR DR SR S D