The Composition of Air
Air is a mixture of gases, primarily consisting of nitrogen, oxygen, and traces of other elements. The exact composition of air can vary slightly depending on factors such as location and altitude.
Determining Nitrogen Content
To determine the amount of nitrogen in air, one can employ a method known as the Kjeldahl method. This method involves digesting a sample of air in a concentrated sulfuric acid solution to convert nitrogen into ammonium sulfate. The nitrogen content can then be calculated based on the amount of ammonium sulfate present.
Historical Significance
The discovery of nitrogen in air is credited to the Scottish chemist Daniel Rutherford in 1772. Rutherford conducted experiments isolating a component of air that did not support combustion or respiration, which he named “noxious air” or nitrogen.
Conclusion
In conclusion, the approximate composition of air is about 78% nitrogen. This value can be confirmed through methods such as the Kjeldahl method, which allows for the accurate determination of nitrogen content in air.