Principle

A quiescent eudiometer is inserted into the glass jacket and the glass jacket is filled with cold water. Gas mixtures composed of hydrocarbons and oxygen are injected into the eudiometer and burn there continuously at the constant sparking of the ignition spark gap. The water formed by the reaction condenses on the cool walls of the eudiometer. For this reason, the volume between the moving plunger and the fixed plunger with the ignition system after combustion is smaller than the volume of the gas mixture originally injected. In a second part of the experiment, the eudiometer in the glass jacket is heated up to over 100°C. The water formed during combustion can no longer condense on the hot eudiometer walls. In most cases, even after conversion to standard conditions, the volume recorded then is greater than the volume of the gas that was injected. The easiest way to convert the volumes to standard conditions is with a nomogram. The measurement data obtained in this way can be used to derive the empirical formulas of gaseous hydrocarbons experimentally.


Tasks

Investigate the chemical formula for methane, ethane and propane.

 

What you can learn about


Stoichiometry

Chemical formula