1. 11-4 Homework11-4 Homework 1)Nickel (II) Phosphate 2)Silver bromide 3)Tin (IV) chloride 4)Ammonium sulfide 5)Mercury (II) fluoride 6)Magnesium nitride 7)Bismuth iodide 8)Ammonium sulfate 9)Zinc carbonate 10)Copper (I) sulfide

2. 11/4 Homework:11/4 Homework: 1) Ni 3 (PO 4 ) 2 6) Mg 3 N 2 2) AgBr7) BiI 3 3) SnCl 4 8) (NH 4 ) 2 SO 4 4) (NH 4 ) 2 S 9) ZnCO 3 5) HgF 2 10) Cu 2 S

4. Law of Conservation of Matter:  Matter cannot be created or destroyed.  AMOUNT OF REACTANTS = AMOUNT OF PRODUCTS ! ! ! !

5. Guidelines for Balancing Chemical Equations:  1) Do NOT change the subscripts !  2) Every element MUST have the same amount of atoms on both sides of the equation.  3) To balance, coefficients (numbers) are added in front of the chemical formula until we have the same atom amount on both sides of the equation.  4) Once a coefficient is added, go back and check the rest of the equation  5) Balance every element EXCEPT Hs and Os. Then balance Hs, Os are balanced last. Balance Hs with an EVEN number  6) CHECK EQUATION TO BE SURE EVERYTHING BALANCES/CANCELS OUT ON BOTH SIDES ! ! !

6. Example 1:Example 1: Mg + HCl  MgCl 2 + H 2

7. Example 2:Example 2: KI (aq) + Pb(NO 3 ) 2  KNO 3 + PbI 2

8. Example 3:Example 3: FeI 3 + K 2 SO 4  KI + Fe 2 (SO 4 ) 3

9. Practice  1) Zn + CrCl 3  CrCl 2 + ZnCl 2  2) Cu + H 2 SO 4  CuSO 4 + SO 2 + H 2 O  3) LiAlH 4 + H 2 O  LiOH + Al(OH) 3 + H 2  4) CaSO 4 + Al(NO 3 ) 3  Ca(NO 3 ) 2 + Al 2 (SO 4 ) 3

10. Homework  Worksheet on Balancing Equations