1. Chemical Equations EQ: What are the reactants and products of a chemical reaction? SPI 0807.9.10

2. What’s a Chemical Reaction? Chemical Reaction process of a substance completely changing to a different substance with different properties.

3. Equations are made up of chemical symbols and formulas. Chemical Symbol Shorter way to write an element’s name. Examples: – H: Hydrogen – O: Oxygen – Fe: Iron

4. Chemical Formula combination of chemical symbols and numbers to represent a substance. It’s an easy way to write molecules and compounds. Examples: – H 2 O: Water – CO 2 : Carbon Dioxide

5. Counting Numbers of Elements and Atoms

6. NameChemical Formula Number of elements Total number of atoms Baking Soda NaHCO 3 ??

7. NameChemical Formula Number of elements Total number of atoms Water H2OH2O ??

8. Subscript Subscript the small # to the right of the element that tells the # of atoms Applies to only the element directly before it!

9. Examples of subscripts: –H2O–H2O – SO 4 – Ca(OH) 2

10. H2OH2O C 6 H 12 O 6 MgCl 2 C 12 H 22 O 11 Ca(OH) 2

11. Take inventory… 1. CO 2 2. H 2 O 3. NaClF 4

12. Coefficients Coefficients large # to the left of the element. Applies to the whole molecule!

13. Examples of coefficients: – 2H 2 O – 4SO 4 – 3Ca(OH) 2

14. 2NH 3 4NaClO 2CaCO 3

15. Take inventory of the following compounds: 1. 4 NaCl 2. 6 CO 2 3. 2 H 2 O

16. CH 4 3CO 3 2Na 2 OH 3

18. 3P 2 O 5 C 3 (FO 4 H 2 ) 2 2Ca(H 2 PO 4 ) 2 Take inventory of the following compounds:

19. EQ: What are reactants and products in a chemical equation?? SPI 0807.9.10 Reactants what you start with Products what you end with

21. REACTANTSPRODUCTS BEFORE THE ARROW AFTER THE ARROW

22. Copy this equation. Circle the REACTANTS and underline the PRODUCTS.

24. How many atoms of each element are there? CH 4 + O 2 → CO 2 + H 2 O

25. CH 4 + 2O 2  CO 2 + 2H 2 O

26. H 2 CO 3  H 2 O + CO 2

27. NH 4 OH  NH 3 + H 2 O

28. The Law of Conservation of Mass EQ: What is the Law of Conservation of Mass? SPI 0807.9.11

29. The Law of Conservation of Mass Law of conservation of Mass states that mass cannot be created or destroyed! 4Na + 2Cl 2  4NaCl

32. This is important when we balance equations… An equation is balanced when the # of atoms in the reactants are = to the # of atoms in the products.

33. Na + Cl 2  2NaCl Is this a balanced equation?

34. 6 CO 2 + 6 H 2 O  C 6 H 12 O 6 + 3 O 2 Is this a balanced equation?

36. You balance an equation by changing the coefficients, not the subscript!

37. Balance this equation. ___ Mg + ___ O 2 ___ MgO

38. Balance the equation. ___ H 2 O 2 ___H 2 O + ___ O 2

39. __ Fe + __S → __FeS

40. __H 2 + __O 2 → __H 2 O

41. __Mg + __O 2 → __MgO

42. _Ca + _H 2 O → _Ca(OH) 2 + _H 2

43. ___ NH 4 NO 3  ___ N 2 O + ___ H 2 O

44. ___BKClO 3  ___BKCl + ___BO 2

45. ___ C 3 H 8 + ___O 2  ___ CO 2 + ___ H 2 O

46. __ Al 2 O 3 + __ Fe  __ Fe 3 O 4 + __ Al

47. ___ P 4 O 10 + ___H 2 O  ___H 3 PO 4

48. __Al + __H 2 SO 4  __Al 2 (SO 4 ) 3 + __H 2

49. __Be 2 C + __H 2 O  __Be(OH) 2 + __CH 4

50. ___ Fe + ___ O  ___ Fe 2 O 3

51. __S + __HNO 3  __H 2 SO 4 + __NO 2 + __H 2 O

52. __NH 3 + __CuO  __Cu + __N 2 + __H 2 O

53. __Cu + __HNO 3  __Cu(NO 3 ) 2 + __NO + __H 2 O

54. Al 2 (SO 3 ) 3 + NaOH  Na 2 SO 3 + Al(OH) 3