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Guaranteed reagents, low impurity content, high purity, suitable for sophisticated analysis and research work. Analytical pure and chemically pure reagents, suitable for general analytical research and teaching experiments. In addition to the reagent GR, analytical reagent AR, chemically pure reagent CP, and experimental reagent LR, there are special reagents suitable for a certain aspect, such as "reference reagent", "chromatography reagent", "biochemical reagent", etc. There are also "high purity reagents", which are subdivided into high purity, ultra pure, spectrally pure reagents.
In addition, there are chemical industrial products that are widely used in industrial production, as well as food-grade products that can be eaten.
The reference reagent is the reference material used in the quantitative analysis to calibrate the standard solution; as the name implies, the spectrally pure reagent is used for spectroscopic analysis; the chromatographically pure reagent is used for chromatographic analysis; and the biochemical reagent is used for various biochemical experiments. The various grades of reagents and industrial products vary greatly in price due to their purity. The price between industrial products and guaranteed reagents can vary by a factor of ten. Therefore, under the premise of meeting the experimental requirements, the principle of saving should be considered and the reagent of the appropriate specification should be selected.