1. The process by which one or more substances are changed into one or more different substances CHEMICAL REACTIONS

2. Word Equations To write a word equation, 1. Write the names of the reactants to the left of the arrow separated by plus signs; 2. Write the names of the products to the right of the arrow, also separated by plus signs. Reactant + Reactant  Product + Product

3. EXAMPLE Methane + Oxygen  Carbon dioxide + Water

5. EXAMPLE 2 Iron + Oxygen  Iron(III) Oxide

6. EXAMPLE 3 Hydrogen Peroxide  Water and Oxygen

7. Skeleton Equations Write the formulas of the reactants to the left of the yields sign (arrow) and the formulas of the products to the right. A skeleton equation is a chemical equation that does not indicate the relative amounts of the reactants and products. Here is the equation for rusting: Fe + O 2  Fe 2 O 3

8. Formula Writing Practice WS

9. Catalyst A catalyst is a substance that speeds up the reaction but is not used up in the reaction Without catalyst With Catalyst

10. Important Symbols

11. Balancing Chemical Equations To write a balanced chemical equation, 1. Write the skeleton equation 2. Use coefficients to balance the equation so that it obeys the law of conservation of mass.  Remember you want the same number of atoms of each element on each side of the equation.

12. Example

13. Example 2

14. Example 3 -- Try on your own!!! Write a balanced chemical equation for the reaction in which sodium hydroxide and calcium bromide react to produce solid calcium hydroxide and sodium bromide. (The reaction occurs in water.) NaOH(aq)+CaBr 2 (aq) Ca(OH) 2 (s)+NaBr(aq) 2NaOH(aq)+CaBr 2 (aq) Ca(OH) 2 (s)+2NaBr(aq)

15. Summary Write a skeleton equation Count atoms Add/adjust coefficients Reduce coefficients to lowest possible ratio Check your work

16. Warm Up!! _____NaClO 3 → ____ NaCl + __O 2

17. Chemical Equations from Names Magnesium and Hydrogen Chloride produce Hydrogen and Magnesium Chloride Calcium Hydroxide and Lithium Chloride produce Lithium Hydroxide and Calcium Chloride Decompose Copper (II) oxide into Copper and Oxygen Aluminum and Iron (III) oxide produce iron and aluminum oxide combustion of Butane (C 4 H 10 ) in air to produce carbon dioxide and water

18. Warm Up ___AgNO 3 + __Ni  __Ni(NO 3 ) 2 + __Ag

19. The Five Types of Reactions Chemical Reactions Synthesis Decomposition Single Replacement Double Replacement Combustion

20. Spongebob Chemistry

21. Chemistry with A + B  AB Synthesis Reactions

22. 1. Synthesis Reactions (Combination) Two or more reactants produce one product Examples: NH 3 + HCl  NH 4 Cl H 2 + O 2  H 2 O Ag + S  Ag 2 S Al + Cl 2  AlCl 3

23. Chemistry with AB  A + B Decomposition Reactions

24. 2. Decomposition One reactant produces two or more products Examples Ag 2 O  Ag +O 2 PCl 5  PCl 3 +Cl 2 H 2 O 2  H 2 O +O 2 CuO  Cu +O 2

25. Chemistry with AB + C  AC + B Single Replacement

26. 3. Single Replacement One element replaces another element Must consult the activity series

27. 3. Single Replacement One element and one compound producing a different element and compound Examples Fe + H 3 (PO 4 )  H 2 + Fe 3 (PO 4 ) 2 H 2 + CuO  Cu + H 2 O Zn + HCl  H 2 + ZnCl 2 Cl 2 + KBr  Br 2 + KCl

28. Equations Activity Series Worksheet

29. Chemistry with AB + CD  AD + CB Double Replacement

30. 4. Double Replacement A double-replacement reaction is a chemical change involving an exchange of positive ions between two compounds. Examples: Al(NO 3 ) 3 + NaOH  Al(OH) 3 + NaNO 3 PbCl 2 + Li 2 SO 4  PbSO 4 + LiCl ZnBr 2 + AgNO 3  Zn(NO 3 ) 2 + AgBr BaCl 2 + KIO 3  Ba(IO 3 ) 2 + KCl

31. 4. Double replacement Three main products of a double replacement reaction Precipitate (solubility table) Water Gas

32. 5. Combustion A combustion reaction Chemical change Element or a compound reacts with oxygen Producing energy in the form of heat and light

33. 5. Combustion A hydrocarbon reacts with oxygen to produce carbon dioxide and water Examples: CH 4 + O 2  CO 2 + H 2 O C 6 H 12 O 6 + O 2  CO 2 + H 2 O