Any section of chemistry involves the use of certain chemicals. Given the fact that reagents are substances that can cause serious harm to human he alth, certain requirements are imposed on their storage.
7 group
Chemical reagents of this group have increased toxicity, so there are certain requirements for their placement. They are located in a special safe located in the laboratory. The assistant has the key to it, as well as the chemistry teacher.
In educational schools, the storage of chemical reagents is prohibited, and in the laboratories of higher educational institutions, their presence is allowed only with a special order from the head of the educational institution. The laboratory assistant keeps a strict record of the consumption of such substances, making entries in a special journal.
List of inorganic reagents allowed in the school laboratory
Let's list the main inorganic chemicals that are allowed for demonstration experiments in chemistry lessons at school:
- simple substances: metallic sodium, crystalline iodine, liquid bromine;
- caustic soda, oxidesmetals and non-metals;
- s alts, including complex compounds, dichromates and chromates;
- acid solutions.
Organic matter
Let's note the organic reagents and substances that a chemistry teacher can use in the formation of practical work skills in schoolchildren:
- aniline;
- organic acids;
- benzene;
- phenol;
- formalin.
Reagent safe requirements
A safe installed in laboratory chemistry, designed to store group 7 reagents, is most often made from solid sheets of metal. It is also allowed to install a wooden structure if the outside of the safe is upholstered with iron, the thickness of which will be at least 1 mm.
There are requirements for the location of the safe. Given that reagents are sources of increased danger, you need to choose a place under the safe so that it can be easily taken out in the event of a fire.
Typical List of Substances with High Physiological Activity
Among the reagents that have similar properties, we can mention metallic zinc, calcium, lithium, calcium oxide and hydroxide, metal nitrates, potassium iodide, potassium permanganate, zinc compounds. Such reagents are hazardous substances, therefore experiments with them are allowed only under the direct supervision of a teacher.
Also included in the list are organic substances such as diethyl ether, acetone, alcohols, cyclohexane, chloroform, crude oil. Such reagents are substancesthat have an effect on the human nervous system, therefore they are excluded from the list of chemicals used in ordinary educational schools for practical work and laboratory experiments.
In the classroom, only 8 groups of reagents are allowed (under lock and key), which are used during practical work and laboratory experiments. Such reagents are substances that are safe for the he alth of children. For example, a solution of sodium chloride, potassium sulfate, calcium chloride.
Storage guidelines for small schools
In small rural schools that do not require a special area for a laboratory room, special attention should be paid to the storage of chemical reagents. For example, an acid reagent in which the concentration of the active substance exceeds 50 percent should be placed in a closed and tied plastic bag.
Alkalis in a solid state of aggregation should be at a considerable distance from acids, with the obligatory preservation of the factory packaging. An opened bottle of caustic soda or potassium should be tightly closed, then placed in a plastic bag or a jar that is tightly closed with a cork.
Only aqueous ammonia and hydrochloric acid have a high vapor pressure, so it is important to check the tightness of their packaging. As additional security measures when working with such reagents, the use of additional sealing plugs, plastic bags per jar is considered.
If there is no space for separate placement of reagents of groups 2, 5, 6, their joint arrangement in one cabinet is allowed. At the same time, a separate shelf must be allocated for each group. The best option would be to place reagents of group 5 on the top shelf, below you can put jars with substances of group 6, put reagents of group 2 in the lower part of the cabinet.
Conclusion
In any educational institution that is supposed to use chemical reagents for lessons and extracurricular activities, there is a special instruction according to which a certain space is allocated for them. The classic laboratory sectional cabinets used to house chemicals are lined with modern polymer materials that are resistant to the negative effects of aggressive environments.
In the absence of such a protective lining, it is important to cover all the internal parts of the cabinet with oil paint in 2-3 layers, make sides on the shelves, the height of which should be 3 cm.
In order to protect the shelves from water ingress, several layers of polyethylene film are laid on them. Placement of furniture in laboratory chemistry is carried out with strict observance of fire safety rules.
On the wall of the laboratory or on the door of the chemistry room, there must be labor protection instructions approved and signed by the director of the educational institution, bearing the seal of the organization.
