The classification of analytical chemistry is diverse, and the analysis process usually includes: sampling, sample processing and decomposition, separation and enrichment, selection of analytical methods and analytical determination, calculation and evaluation of analytical results.
1. Sample collection, treatment and decomposition
The sample collection and preparation must ensure that the obtained sample is a representative sample, that is, the composition of the analysis sample can represent the average composition of the whole batch of materials. Otherwise, no matter how serious and accurate the subsequent analysis and determination are, the results obtained will be meaningless, and even because the analysis results provided are not representative, it will cause serious consequences for practical work.
2. Common separation and enrichment methods in analytical chemistry
Complex samples often contain multiple components. When measuring one of the components, other coexisting components often cause interference, so try to eliminate the interference. The use of masking agents to eliminate interference is an effective and simple method. Without a suitable masking method, it is necessary to separate the measured components from the interfering components. Commonly used methods include precipitation separation, extraction separation, ion exchange separation and chromatography separation. Separation and determination are often carried out continuously or simultaneously.
3. Analytical assays
According to the content of the measured components and the requirements for the accuracy of the analysis results, an appropriate analysis method should be selected for analysis and determination. When choosing the correct analytical method for determination, the principle, accuracy, sensitivity, selectivity and applicable range of various analytical methods should be considered.
4. Calculation and evaluation of analysis results
Calculate the content or concentration of the relevant components in the sample according to the mass of the sample, the measured signal, the data and the measurement relationship of the relevant reaction in the analysis process.
