CHNanalüüsiga

CHNanalüüsiga refers to the process of elemental analysis, specifically determining the mass percentages of carbon (C), hydrogen (H), and nitrogen (N) within a given sample. This technique is fundamental in organic chemistry and related fields for identifying and characterizing unknown compounds, as well as verifying the purity of synthesized substances.

The analysis typically involves combusting a precisely weighed sample in an oxygen-rich environment. The combustion completely oxidizes the carbon in the sample to carbon dioxide (CO2), the hydrogen to water (H2O), and the nitrogen to nitrogen gas (N2) or other nitrogen oxides which are then reduced to N2. These gaseous products are then quantitatively measured. For instance, the CO2 is absorbed by a suitable reagent, and the increase in mass of the absorbent corresponds to the amount of carbon in the original sample. Similarly, water can be collected and weighed, or its formation detected. Nitrogen is often measured directly as a gas.

The data obtained from CHN analysis is expressed as percentages by mass. These percentages are then used to calculate the empirical formula of a compound, which represents the simplest whole-number ratio of atoms in a molecule. By comparing the experimentally determined percentages with those calculated for possible molecular formulas, chemists can deduce the identity of the substance. CHN analysis is a highly sensitive and accurate method, crucial for confirming the composition of organic molecules.