What do you mean by AR, GR, CP and PT in chemical reagents?

AR, GR, CP and PT in chemical reagents represent the quality index level of chemical reagents. What they mean is:

Analytical pure reagent: abbreviated as AR, also known as secondary reagent. Generally, bottles are labeled with red. It has high content of main components, high purity and less interfering impurities, and is suitable for industrial analysis and chemical experiments. Equivalent to foreign ACS level (American Chemical Association standard)

Guarantee reagent: abbreviated as GR, also known as first-class reagent. Generally, bottles will be labeled with green (so-called excellent purity). The main components are high in content and purity, which is suitable for accurate analysis and research, and some of them can be used as reference materials.

Chemically pure reagent: abbreviated as CP, also known as tertiary reagent. Generally, bottles are labeled with dark blue. The main components are high in content and purity, and there are interfering impurities, so it is suitable for chemical experiments and synthetic preparation.

Reference reagent: abbreviated as PT, specially used as reference substance, which can directly prepare standard solution.

Extended data:

Other levels of chemical reagents:

AAS atomic absorption spectrometry, BC biochemical reagent, BP British Pharmacopoeia, BR biochemical reagent, BS biological stain, CR chemical reagent, EP ultrapure, FCP chromatography, FMP microscope, FS synthesis, GC gas chromatography, GR ultrapure reagent, HPLC high pressure liquid chromatography, id indicator, IR infrared absorption spectrometry, MAR microanalysis reagent, NMR nuclear magnetic resonance spectroscopy, OAS organic analysis standard.

PA analysis, Pract practice, PT reference reagent, Puriss ultra-pure, Purum pure, SP spectrum pure, Tech industrial, TLC thin-layer chromatography, UP ultra-pure, USP USP, UV spectrophotometry pure, teaching reagent, MI medical grade, I industrial grade, F food grade, M cosmetic grade, S solid, L liquid, E fine product, C crude product.

Safe use of chemical reagents:

1, flammable and explosive chemical reagent

Generally, chemical reagents with flash point below 25℃ are classified as flammable chemical reagents, and most of them are highly volatile liquids, which can burn when exposed to open fire. The lower the flash point, the easier it is to burn. Common flash points below -4℃ are petroleum, chloroethane, condensed ethane, ether, gasoline, carbon dioxide, propylene, benzene, ethyl acetate and methyl acetate.

Flammable reagents can also cause explosions when burned violently. Some solid chemical reagents, such as nitrocellulose, picric acid, trinitrotoluene, trinitrobenzene, azide or overlapping compounds and oxalate, are explosive in themselves. When exposed to high temperature or open flame, they are easy to burn or decompose and explode. When using these chemical reagents, never directly heat them. When using these chemical reagents, we should also pay attention to no open flames around.

The experimenters who use flammable chemical reagents should wear necessary protective equipment, preferably protective glasses.

2. Toxic chemical reagents

General chemical reagents are toxic to human body, so it is necessary to avoid inhaling a lot when using them. Wash your hands, face, shower and change your work clothes in time after using the reagent in the public performance. For some chemical reagents that can be poisoned to death by inhaling or eating a small amount, the lethal dose (LD50) in biological test is less than 50mg/kg, which is called highly toxic chemical reagent.

Such as cyanide such as potassium cyanide and sodium cyanide, arsenic trioxide and some arsenic compounds, mercury dichloride and some mercury salts, sulfuric acid and dimethyl ester. When using a chemical reagent with ambiguous properties, we must know its LD50. For some commonly used highly toxic chemical reagents, we must understand the first-aid treatment methods when these chemical reagents are poisoned. Highly toxic chemical reagents must be kept by special personnel and the usage must be strictly controlled.

3, corrosive chemical reagents

When any chemical reagent comes into contact with skin, mucous membrane, eyes and respiratory organs, it should be cleaned in time, especially the chemical reagent (whether liquid or solid) which is extremely corrosive to skin, mucous membrane, eyes and respiratory organs.

Such as: various acids and bases, phosphorus trichloride, phosphorus oxychloride, bromine, phenol, hydrazine hydrate, etc. Avoid contact with skin, mucous membrane, eyes and respiratory organs, and be sure to know the first-aid treatment methods of contact with these corrosive chemicals before use. If the acid spills on the skin, it should be washed with dilute lye.

4, strong oxidizing chemical reagents

Strong oxidizing chemical reagents are peroxides or oxyacids and their salts with strong oxidizing ability. Such as: peroxy acid, ammonium nitrate, potassium nitrate, perchloric acid and its salts, repetitive acid and its salts, permanganate and its salts, benzoic acid peroxide, peracid, phosphorus pentoxide, etc.

Strong oxidizing chemical reagents can release oxygen and explode under appropriate conditions, forming explosive mixtures with combustible substances such as organic magnesium, aluminum, zinc powder and sulfur. Some of them may also explode in water. When using this kind of strong oxidizing chemical reagent, the ambient temperature should not be higher than 30℃ and the ventilation is good. Do not use (heat) with organic substances or reducing substances.

5, radioactive chemical reagents

When using such chemical reagents, protective measures must be taken according to the use method of radioactive substances.

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