Differences and characteristics between the hottes

The difference and characteristics between instrumental analysis and chemical analysis

chemical analysis refers to a kind of analysis method that uses chemical reaction and its metrological relationship to determine the composition and content of the tested substance. Chemical reagent, balance and some glassware are needed for determination

instrument analysis (modern analysis method or physical analysis method): it is an analysis method based on the physical or physicochemical properties of substances. It is a control method that takes a certain measurement as the feedback signal and adjusts the control output in real time according to the size of the feedback signal and its PID parameters. This kind of method is usually used to measure physical quantities such as light, electricity, magnetism, sound and heat to obtain the analysis results, and the measurement of these physical quantities generally requires the use of more complex or special instruments and equipment, so it is called "instrumental analysis". In addition to qualitative and quantitative analysis, instrumental analysis can also be used for structure, valence state, state analysis, micro area and thin layer analysis, trace and ultra trace analysis, etc., which is the development direction of analytical chemistry

compared with chemical analysis, instrumental analysis has the following characteristics:

1 Level L, or even lower. It is suitable for the determination of trace, trace and ultra trace components. g. High sensitivity, detection limit can be reduced. For example, the sample dosage is reduced from ml and mg of chemical analysis to

2 of instrumental analysis Good selectivity. Many instrumental analysis methods can choose or adjust the determination conditions so that the coexisting components do not interfere with each other

3. The operation is simple, the analysis speed is fast, and it is easy to realize automation

4. The relative error is large. In the most widely used conventional plastic granulator equipment, chemical analysis can generally be used for constant and high content component analysis, with high accuracy and error less than a few thousandths. The relative error of most instruments is relatively large, which is generally 5% except that it affects the different center of the jaw. It is not suitable for constant and high content component analysis

5. Instrumental analysis requires expensive special instruments

the two have the same points:

1. Both can be used as qualitative and quantitative analysis methods. Chemical analysis can generally be used for constant and high content component analysis, with high accuracy and error less than a few thousandths. The relative error of most instruments is relatively large, generally 5%, which is not suitable for constant and high content component analysis

2. The analysis principle is consistent