Balancing Chemical Equations

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
1.       H2 + O2 H2O

2.       H2 + N2 NH3

3.       Al2O3 Al + O2

4.       AlCl3 Al + Cl2

5.       S8 + O2 SO2

6.       C2H6 + O2 CO2 + H2O

7.       CaBr2 + KOH → Ca(OH)2 + KBr

8.       P4 + O2 P2O5

9.       Cu + S8 CuS

10.       Al + Br2 AlBr3

11.       Cr + O2 Cr2O3

12.       NaClO3 NaCl + O2

13.       AlBr3 + Cl2 AlCl3 + Br2

14.       Na + H2O → NaOH + H2

15.       AlI3 + HgCl2 AlCl3 + HgI2

16.       Ca(OH)2 + H2SO4 CaSO4 + H2O

17.       BaCl2 + H2SO4 BaSO4 + H2O

18.       C3H8 + O2 CO2 + H2O

19.       C2H2 + O2 CO2 + H2O

20.       C6H6 + O2 CO2 + H2O