The Joy of

Balancing Equations

What we already know…

• Coefficient 2CaCl2

The 2 tells you that there are 2Ca and 4Cl

• CaCl2 Subscript

The little two tells you that there are 2 Cl.

A + B = Not chemically bonded, so its not a compound!

AB = This is a compound which is chemically bonded.

NEVER ADD SUBSCRIPTS!

So…Let’s practice some more!

Helpful hints to be successful with Balancing

Equations•Remember to… • Draw your line separating the

“reactants” from the “products”.• Make a list of the elements on each side.• “Attack” the compounds first!• Save the “Elements” for last. • If you hit a “Dead End” remember to go

back and double your coefficients. Try it!• Double check your work so that it is

equal on both sides of the equation.

Balancing Equations Warm up

Git-R-Done!1.H2 + O2 H2O

2. HgO Hg + O2

3. CO2 + H2O C6H12O6 + O2

4. Zn + HCl ZnCl2 + H2

Balancing Equations Warm up Answers

1.2H2 + O2 2H2O

2. 2HgO 2Hg + O2

3. 6CO2 + 6H2O C6H12O6 + 6O2

4. Zn + 2HCl ZnCl2 + H2

Balancing Equations Classwork

5. SiCl4 + H2O H4SiO4 + HCl

6. Na + H2O NaOH + H2

7. H3PO4 H4P2O7 + H2O

*8. C7H6O2 + O2 CO2 + H2O

Balancing Equations Classwork

5. SiCl4 + 4H2O H4SiO4 + 4HCl

6. 2Na + 2H2O 2NaOH + H2

7. 2H3PO4 H4P2O7 + H2O

8. 2C7H6O2 + 15O2 14CO2 + 6H2O

Balancing Equations Classwork

9. H2SO4 + HI H2S + I2 + H2O

10. Al + HCl AlCl3 + H2

11. PCl5 + H2O HCl + H3PO4

Balancing Equations Classwork Answers

9. H2SO4 + 8HI H2S + 4I2 + 4H2O

10. 2Al + 6HCl 2AlCl3 + 3H2

11. PCl5 + 4H2O 5HCl + H3PO4

Balancing Equations Homework

12. Mg + N2 Mg3N2

13. Fe + H2O Fe3O4 + H2

14. NaOH + Cl2 NaCl + NaClO + H2O

15. N2 + H2 NH3

16. C3H6 + O2 H2O + CO2

17. N2 + O2 N2O

Balancing Equations Homework Answers

12. 3Mg + N2 Mg3N2

13. 3Fe + 4H2O Fe3O4 + 4H2

14. 2NaOH + Cl2 NaCl + NaClO + H2O

15. N2 + 3H2 2NH3

16. 2C3H6 + 9O2 6H2O + 6CO2

17. 2N2 + O2 2N2O

Balancing Equations Warm up

18. Al + FeO Al2O3 + Fe

19. Fe2O3 + H2 Fe + H2O

20. K2O + H2O KOH

21. H2O2 H2O + O2

Balancing Equations Warm up Answers

18. 2Al + 3FeO Al2O3 + 3Fe

19. Fe2O3 + 3H2 2Fe + 3H2O

20. K2O + H2O 2KOH

21. 2H2O2 2H2O + O2

Balancing Equations Classwork

22. Al + O2 Al2O3

23. C7H16 + O2 CO2 + H2O

24. Na2O2 + H2O NaOH + O2

25. SiO2 + HF SiF4 + H2O

26. N2 + H2 NH3

27. KClO3 KCl + O2

28. H3AsO4 As2O5 + H2O

Balancing Equations Classwork Answers

22. 4Al + 3O2 2Al2O3

23. C7H16 + 11O2 7CO2 + 8H2O

24. 2Na2O2 + 2H2O 4NaOH + O2

25. SiO2 + 4HF SiF4 + 2H2O

26. N2 + 3H2 2NH3

27. 2KClO3 2KCl + 3O2

28. 2H3AsO4 As2O5 + 3H2O

Balancing Equations Homework

29. KClO3 KClO4 + KCl

30. P4O10 + H2O H3PO4

31. Na2CO3 + HCl NaCl + H2O + CO2

32. K + Br2 KBr

33. P4 + O2 P2O5

34. N2O5 + H2O HNO3

35. Fe2O3 + CO Fe + CO2

Balancing Equations Homework Answers

29. 4KClO3 3KClO4 + KCl

30. P4O10 + 6H2O 4H3PO4

31. Na2CO3 + 2HCl 2NaCl + H2O + CO2

32. 2K + Br2 2KBr

33. P4 + 5O2 2P2O5

34. N2O5 + H2O 2HNO3

35. Fe2O3 + 3CO 2Fe + 3CO2

Challenging Equations

36. H3BO3 H4B6O11 + H2O

37. H2S + Cl2 S8 + HCl

38. S8 + O2 SO3

39. C3H8 + O2 CO2 + H2O

40. FeS2 + O2 Fe2O3 + SO2

Challenging Equations Answers

36. 6H3BO3 H4B6O11 + 7H2O

37. 8H2S + 8Cl2 S8 + 16HCl

38. S8 + 12O2 8SO3

39. C3H8 + 5O2 3CO2 + 4H2O

40. 4FeS2 + 11O2 2Fe2O3 + 8SO2

More Challenging Equations

41. C2H6 + O2 CO2 + H2O

42. H3PO4 + KOH K3PO4 + H2O

43. CaCO3+H3PO4 Ca3(PO4)2+H2CO3

44. Pb(OH)4+Cu2O PbO2+CuOH

45. Sn(NO2)4+Pt3N4 Sn3N4+Pt(NO2)4

More Challenging Equations Answers

41. 2C2H6 +7O2 4CO2 + 6H20

42. H3PO4 + 3KOH K3PO4 + 3H2O

43. 3CaCo3+2H3PO4 Ca3(PO4)2+3H2CO3

44. Pb(OH)4+2Cu2O PbO2+4CuOH

45. 3Sn(NO2)4+Pt3N4 Sn3N4+3Pt(NO2)4

Vinegar Reacting With Baking Soda

CH3COOH + NaHCO3 H2O + NaOCOCH3 + CO2