| Balance | Answer |
| 2 Fe +__ HCl --> 2 FeCl 3 + 3 H 2? | |
| __Na 2 O 2--> Na 2 O + 1 O 2? | |
| 2 Na + 2 HCl--> __ NaCl + 1 H 2? | |
| 4 Al + __ O 2 --> 2 Al 2 O 3? | |
| __N 2 + 3 H 2 --> 2 NH 3? | |
| 4 Al + 3 O 2--> __Al 2 O 3? | |
| 2 CaCO 3 --> 2 Ca + 2 C + __ O 2? | |
| __SiO 2 + 2 C --> 1 Si + 2 CO? | |
| __ Al + 3 I 2 --> 2 Al I 3? | |
| 2 H 2 + __O 2 --> 2 H 2 O? | |