Intro to Chemistry Double Displacement Notes

Intro to chemistry notes over Double Displacement reactions

1. DOUBLE DISPLACEMENT Essential Question: How do we predict the products of a double displacement reaction?

2. WILL THIS BE SINGLE OR DOUBLE DISPLACEMENT? HOW DO YOU KNOW? NaBr + Ca(OH) 2 →

3. VERY similar to predicting the products of single displacement. The cations will switch places (but you can see it as the anions switching places too!) THIS UNIT IS ALL ABOUT DOUBLE DISPLACEMENT

4. I PROMISE I won’t forget…. 1. 2. COMPOUNDS: CRISS-CROSS THE CHARGES ELEMENT: HOFBrINCl Only ONE of our previous promises is relevant this unit. Why is the other promise irrelevant in this unit?

5. EXAMPLE 1 ___ NaCl + ____ H 2 SO 4 → ____ ____________ + ____ ____________

6. EXAMPLE 2 ___ AgNO 3 + ____ BaCl 2 → ____ ____________ + ____ ____________

7. YES! STOICHIOMETRY!

8. DOUBLE DISPLACEMENT & STOICHIOMETRY A chemist needs 75.0 grams of copper(II) chloride. What mass of copper(II) sulfate will she need to react? _____ CuSO 4 + _____ H Cl → _____ CuCl 2 + _____ H 2 SO 4

9. DOUBLE DISPLACEMENT

10. GRAB A DRY-ERASE BOARD, ERASER & MARKER!

11. WHITEBOARD PRACTICE #1 ODD # PARTNER EXPLAINS, EVEN # PARTNER LISTENS ___ Ca(OH) 2 + ____ H 3 PO 4 → ____ ____________ + ____ ____________ HOH Ca 3 (PO 4 ) 2 3 2 6 1

12. WHITEBOARD PRACTICE #2 ODD # PARTNER LISTENS, EVEN # PARTNER EXPLAINS ___ Pb(NO 3 ) 2 + ____ KI → ____ ____________ + ____ ____________ PbI 2 KNO 3 1 2 1 2

13. WHITEBOARD PRACTICE #3 ___ K 2 CO 3 + ____ BaCl 2 → ____ ____________ + ____ ____________ KCl BaCO 3 1 1 2 1

14. WHITEBOARD PRACTICE #4 ___ Al 2 (SO 4 ) 3 + ____ Ca 3 (PO 4 ) 2 → ____ __________ + ____ __________ AlPO 4 CaSO 4 1 1 2 3

15. WHITEBOARD PRACTICE #5 ___ FeCl 2 + ____ Ba(OH) 2 → ____ __________ + ____ __________ Fe(OH) 2 BaCl 2 1 1 1 1

16. WHITEBOARD PRACTICE #4 How many moles of aluminum hydroxide can be produced if 3.33 moles of magnesium hydroxide reach? 2 AlBr 3 + 3 Mg(OH) 2 → 2 Al(OH) 3 + 3 MgBr 2 BRING IT UP WHEN YOU’RE DONE!

17. LIMITING REACTANT Essential Questions: What does the amount of reactant have to do with the amount of product in a chemical reaction?

18. LIMITING REACTANT Determines the amount of product in an equation. All of the limiting reactant is consumed in a reaction EXCESS REACTANT Extra material which is not consumed in a chemical reaction

19. Take an inventory. Count the particles in each diagram and list them. Before the reaction: # of C atoms: ________ # of S atoms: ________ After the reaction: # of CS 2 atoms: _______ # of C atoms: ______ 4 6 2 4 Which reactant (C or S atoms) is in excess ? Which reactant (C or S atoms) limits the reaction? Sulfur Carbon

20. Take an inventory. Count the particles in each diagram and list them. Before the reaction: # of C atoms: ________ # of S atoms: ________ After the reaction: # of CS 2 atoms: _______ # of C atoms: ______ 4 6 2 4

21. Before the reaction: # of C atoms: ________ # of S atoms: ________ After the reaction: # of CS 2 atoms: _______ # of C atoms: ______ 4 6 2 4 Which reactant (C or S atoms) is in excess ? Which reactant (C or S atoms) limits the reaction? Sulfur Carbon

22. DETERMINING THE LIMITING REACTANT Step 1: Using stoichiometry, solve for amount of product for each reactant. (Use the same product for both!) Step 2: The lowest resulting value is the limiting reactant (LR).

23. EXAMPLE 1 2 C 2 H 6 + 7 O 2 → 4 CO 2 + 6 H 2 O Suppose you have 3.00 moles of ethane (C 2 H 6 ) and 9.00 moles of oxygen gas. Which is the limiting reactant? How many moles of CO 2 can be made?