Question

You may have noticed that water sometimes drips from an exhaust pipe of a car as it is running.Is this evidence that there is at least a small amount of water originally present in the gasoline?Explain.

Short answer

It is a false statement that the production of water vapor on the exhaust pipe happens due to the presence of a small amount of water in gasoline.

Step-by-step solution

Combustion of gasoline

Gasoline is a mixture of hydrocarbons. On complete combustion, it releases water vapor. The chemical equation is as shown below:

${\mathbf{\text{C}}}_{\mathbf{n}}{\mathbf{H}}_{\mathbf{m}} \mathbf{+} {\mathbf{O}}_{\mathbf{2}} \to {\mathbf{CO}}_{\mathbf{2}} \mathbf{+} {\mathbf{H}}_{\mathbf{2}}\mathbf{O}$

The combustion of hydrocarbon will result in the production of two products that are,

1. Gaseous carbon dioxide
2. Water

Explanation

The formation of water is due to the chemical reaction that is combustion. This does not mean that water is present in gasoline. If there is any water present in gasoline, then it will not allow the engine to work properly.