Combustion
What is combustion?
- Combustion is the scientific word for burning
- All combustion reactions involve a chemical change in which oxygen reacts with elements or compounds to produce oxides
- Combustion reactions give out heat, so they will always be exothermic reactions
- You need to be able to describe the combustion reactions of magnesium, hydrogen and sulfur
The combustion reactions of Mg, H2 & S
| Element | Observation during combustion | Symbol equation |
| Magnesium |
Intense white flame White powder produced (magnesium oxide) |
2Mg (s) + O2 (g) → 2MgO (s) |
| Hydrogen |
Exothermic Water is produced |
2H2 (g) + O2 (g) → 2H2O (g) |
| Sulfur |
Blue flame Colourless, poisonous gas produced |
S (s) + O2 (g) → 2SO (g) |
Examiner Tip
Combustion reactions can also be classified as oxidation reactions.
