Question

How do you write chemical equations for combustion reactions?

So I have solid barium, solid boron, liquid acetone `C_3H_6O`, and liquid octane `C_8H_18`. I know that a combustion reaction results in `CO_2` + `H_2O`, but I'm just confused on what the text is saying with the formula for combustion being A + `O_2` `rarr` AO.

Answer 1

The combustion of octane `C_8H_18` follows this reaction
`2C_8H_18 + 25O_2 -> 16CO_2 + 18H_2O`

Explanation:

A combustion reaction takes a hydrocarbon and burns it in oxygen to release carbon dioxide and water. A hydrocarbon is a molecule that contains carbon and hydrogen.

The basic equation looks like this.

The combustion of propane `C_3H_8` follows this reaction

`C_3H_8 + 5O_2 -> 3CO_2 + 4H_2O`

The combustion of pentane `C_5H_12` follows this reaction

`C_5H_12 + 8O_2 -> 5CO_2 + 6H_2O`

The combustion of octane `C_8H_18` follows this reaction

`2C_8H_18 + 25O_2 -> 16CO_2 + 18H_2O`

Answer 2

Combustion is when a substance reacts quickly with oxygen producing heat and light.

Explanation:

The general equation for combustion is:

`A + O_2 -> AO`

Magnesium is an example of an element that can undergo a combustion reaction. The reaction of magnesium and oxygen produces a very bright light and quite a bit of heat, burning at a temperature of 3,100 °C.

Here is a quick demonstration showing the combustion of magnesium.

Hope this helps!