| The sparks generated by striking steel against a flint provide the activation energy to initiate combustion in this Bunsen burner. |
| Before the internal combustion engine was adapted for use in fishing boats, human strength was the only means of conquering the seas. |
| The cost of charging an electric car is small compared to that of refuelling a vehicle that runs an internal combustion engine. |
| Most modern stoves are airtight and allow the amount of combustion air that feeds the flame to be controlled. |
| Turn off all combustion appliances such as gas burning furnaces and water heaters. |
| Gasoline combustion causes both local air pollution and emissions of carbon, a greenhouse gas that might affect the future global climate. |
