1. Balancing Equations and Identifying Reaction Types

2. Why do we balance equations?

3. Writing Chemical Equations
Reactants  Products

4. Writing Chemical Equations
Word Equation:
Iron metal reacts with oxygen gas and forms solid iron (III) oxide
Chemical Equation:

5. Writing Chemical Equations
Balanced Chemical Equation:
4 Fe (s) + 3 O2(g) 2 Fe2O3 (s)

6. Balancing Equations Example 1

7. Balancing Equations Example 2

8. Dalton’s Atomic Theory
All elements are composed of indivisible
particles called atoms
Atoms of the same element are identical. The atoms of any one element are different from those of any other element.
Atoms of different elements can physically mix together or chemically combine with one another in simple whole number ratios to form compounds.(law of definite composition)
Chemical rxns occur when atoms are separated, joined, or rearranged. Atoms of one element, however, are never changed into atoms of another element as a result of a chemical reaction.(law of conservation of mass)

9. Balancing Equations Guidelines
1 . Write the correct chemical formulas for the reactants and the products
2. Include states of matter if necessary (s, l, g, aq)

10. Balancing Equations Guidelines
3. Count the number of atoms of each element in the reactants and products
4. Balance the elements one at a time using coefficients; never change subscripts ---see part a,b,c

11. Balancing Equations Guidelines
4a. Treat polyatomic ions appearing on both sides of rxn as one unit and balance first
4b. Balance atoms that appear once on each side of the equation
4c. Balance H and O last

12. Balancing Equations Guidelines
5. Check Work
6. Coefficients should be in lowest possible ratios

13. Balancing Equations Guidelines
Write formulas
States of matter
Count atoms
Balance using coefficients
Check work
Coefficients in lowest ratios?

14. Predicting Products Combination: Mg + O2  Decomposition: Ca(ClO3)2 
Single: Cu + AgNO3 
Double: KI + Pb(NO3)2 
Combustion: CH4 + O2 

15. Predicting Products
1. Combination
Mg + O2 

16. Predicting Products

17. Predicting Products
2. Decomposition
Ca(ClO3)2 

18. Predicting Products
3. Single Replacement
Cu + AgNO3 

19. Predicting Products

20. Predicting Products
4. Double Replacement
KI + Pb(NO3)2 

21. Predicting Products

22. Predicting Products
5. Combustion
CH4 + O2 

23. Reaction Types

24. Reaction Types

25. Balancing Equations Practice
Write a balanced equation for each
of the following chemical reactions:

26. Balancing Equations Practice
Aluminum metal reacts with aqueous hydrochloric acid to form hydrogen gas and aqueous aluminum chloride.

27. Balancing Equations Practice
Acetylene gas (C2H2) burns in a
welding torch with oxygen to form
carbon dioxide and water.
Balancing Equations Practice

28. Balancing Equations Practice
Copper metal and aqueous silver nitrate react to form copper(II) nitrate and silver metal

29. Balancing Equations Practice
Aluminum metal reacts with oxygen to form aluminum oxide

30. Balancing Equations Practice
Barium Chlorate decomposes into barium chloride and oxygen gas

31. Balancing Equations Practice
Balance each equation and tell
what type of reaction it represents.

32. Balance and Identify RXN Type
_Fe + _Br2  _FeBr3
_C6H14+_ O2  _CO2 +_ H2O

33. Complete and balance the following reactions:
SrCO3 
Li + H2O 
Li3PO4 + Zn(NO3)2 
C3H8 + O2 
C2H5OH + O2 

34. Activity Series of Metals Lab
Single Replacement Reactions
= An elements switches places with another element in a compound to form a new compound and element
Example:
2Al + 3Fe(NO3)2  2Al(NO3)3 + 3Fe

35. Activity Series of Metals Lab
Reactivity – the ability of an element to react

36. Activity Series of Metals Lab
Activity Series – list of elements organized according to ease at which elements undergo certain chemical reactions

37. Activity Series of Metals Lab
A reactive metal will replace any metal listed below it in the activity series

39. Will these rxns occur? Li + MgCl2  Pb + AlCl3 
Note: These are single replacement reactions. A + BC  AC + B

40. Activity Series of Metals
Li>K>Ba>Ca>Na>Mg>Al>Mn>Zn>Cr>Fe>
Co>Ni>Sn>Pb>H>Cu>Ag>Hg>Pt>Au