What should be paid attention to in the use of materials based on chemical reagents?

1.the deterioration and denaturation of the material in contact with the surrounding environment;

2.the impact of materials on the environment, such as pollution;

3.Material poison to people***.

Of course, the above articles depend on the specific chemical substances that the material is made of.

1. Storage. 1. Classified storage of toxic or precursor chemical reagents in the drug cabinet, and special personnel are in charge.

Flammable and explosive reagents are placed in explosion-proof reagent cabinets.

Volatile chemical reagents are placed in a ventilated reagent cabinet with an alarm device.

Note that there are chemical reagents that need to be shaded and packaged in brown bottles.

Biochemical reagents are often stored at low temperatures, and it may be necessary to use a low-temperature freezer.

2. The use of chemical reagents follows the principle of safety first, and is easy to use under the condition of ensuring good ventilation in the laboratory.

volatile or toxic reagents, mostly in fume hoods, or in the case of universal fume hoods;

During the experiment, wear goggles.

Wait a minute. 3. Emergency treatment In the process of using reagents, accidentally splash the reagent into the first or eye, there are several treatment methods: water.

Chemical reactions or physical changes will occur, such as heating, first wipe with a clean cotton cloth, and then.

Wash with plenty of water and send to the doctor; If there is no reaction in water, wash it directly with the most clean water, and then send it to the hospital;

It is best to have an emergency eyewash or emergency shower in the laboratory;

It's all about being safe.

Chemical reagents cannot be used as a substitute for drugs because of different production standards, different purities, and different proportions.

1. The purpose of chemical drug production is to cure diseases, and more attention is paid to efficacy and safety, in order to play a better role, there is usually a certain formula, not necessarily pure substances, and the verification of harmful substances is more stringent. Since it is not a pure substance, it cannot be used in chemical reagents.

2. The purpose of chemical reagent production is chemical application, such as laboratory, laboratory, analysis, etc. Generally, it is a pure substance of a certain purity, and the harmful substances contained in it do not affect the experiment, so it cannot be used as a drug.

Conceptual analysis: the so-called chemical reagent is the agent used in chemical experiments; That is, chemical agents required for chemical experiments. The classification of chemical purity and grade can be determined according to the quality standards and scope of application of chemical agents.

It is generally believed that when the principal content, boiling point, melting point, density, refraction, and even ultraviolet, infrared, and nuclear magnetic spectra are known, the purity and scope of application of a substance can be completely determined. The main difference between the content of chemical reagent labels in China and the content of chemical reagent labels in foreign countries.

Access to solid reagents: The spoon must be clean when using solid medicines. Two or more reagents cannot be used at the same time with one medicine spoon.

The spoon must be wiped clean with clean paper after each reagent is taken for the next use. The two ends of the spoon are two large and small spoons, and a large spoon is used when the amount of solids is large, and a small spoon is used when there is a small amount of solids. Liquid reagent access:

Take the reagent from the test nuclear waiter bottle, hold the graduated cylinder (or test tube) in your left hand, and use the thumb to indicate the desired volume scale. Hold the reagent bottle in your right hand (note: the reagent label should be in the palm of your hand to avoid staining the label with the reagent), and slowly inject the liquid into the graduated cylinder to the pointed scale (when reading the scale, the line of sight should be kept level with the lowest part of the concave surface of the liquid (after the figure is poured, the mouth of the reagent bottle should be leaned against the wall of the container, and then the bottle should be vertically adjusted to prevent the reagent from flowing to the outer wall of the bottle.)

If the top of the stopper is not flat, use the index and middle fingers (or middle and ring fingers) to clamp the stopper (or place it on a clean surface dish), never horizontally on the table. After taking the reagent, the original cork should be covered immediately, the reagent bottle should be put back to the original place, and the reagent label should be facing outward, the reagent should be taken according to the required amount, do not need to take more, if you accidentally take out too many reagents, you can only discard, do not make a noise to pour back or put back the original bottle. so as not to stain the reagent.

For details, please refer to:

When using toxic, foul-smelling reagents, they should be handled in a fume hood.

Laboratory safety regime.

1. All work that may produce toxic vapor in the laboratory must be carried out in a fume hood, and there should be good exhaust equipment.

2. When diluting concentrated sulfuric acid, water should not be poured into concentrated sulfuric acid, but concentrated sulfuric acid should be slowly poured into the water and stirred constantly.

3. When taking toxic and foul-smelling reagents, they should be operated in a fume hood; After use, seal the bottle tightly.

4. Dangerous chemical substances shall be classified and stored separately, and reducing reagents and oxidants, acids and alkali corrosives shall not be mixed, and a safe distance shall be kept from each other.

5. Chemical dangerous goods that are flammable, easy to produce toxic gases or are exposed to sunlight should be stored in a cool and ventilated place.

Volatile, toxic reagents such as hydrogen sulfide, ammonia.

d Grignard requirements can not have active hydrogen (water, alcohol, phenol, ether, acid and end alkyne) and active carbonyl (aldehydes, ketones, esters, acid halides, anhydride) a as aldehydes, active carbonyl; b is the terminal alkyne with active hydrogen; c is alcohol, and there is active hydrogen, so only d can.

Grignard reagent is prepared in ether solution, and perhaps the latter two will undergo structural changes at this time, so it is not suitable for Grignard reagent.

Preparation of alkyne Grignard reagents.

rc≡ch + c2h5mgbr→bai rc≡c-mg-br + c2h6

In this reaction, C2H5mgBR can be regarded as a magnesium salt of the magnesium ion of the alkyl negative DU ion, which is stronger in base than the terminal alkyne, so that the hydrogen atom on the alkyne is seized. The alkynes are converted into the corresponding alkyl Grignard reagent.