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Anonymous users2024-02-13Commonly used chemical experimental instruments in junior high school:
1. a graduated cylinder. --If the volume of the liquid is measured, it cannot be heated or filled with a hot solution.
2. The test tube --- hold a small amount of solid, liquid or as a reaction vessel, which can be heated directly.
3. Beaker. Flasks, Erlenmeyer flasks.
- If it contains a liquid reagent, it can be heated directly.
4. Pallet balance.
- Weighing the mass of solids.
5. Funnels--- ordinary funnels, long-necked funnels.
6. Alcohol lamp.
- Heating is used as a heat source.
7. a glass rod.
-It is used for stirring (accelerated dissolution), filtration, drainage or transfer, such as pH determination.
8. a burning spoon.
- Loading solid chemicals for combustion experiments.
10. a thermometer.
-Freshly used high-temperature thermometers should not be rinsed immediately with cold water.
11. a medicine spoon.
- For the use of powder or small granular solid medicines, the spoon should be wiped clean with clean filter paper before each use.
12. Iron frame, iron frame, test tube clamp --- used to fix test tubes.
13. Gas collection cylinders are used --- collect gas.
14. Dropper bottles, fine-mouth bottles--- containing liquid reagents, 15. Jar-mouth bottles--- containing solid reagents.
16. an evaporation dish.
- Heating of evaporated liquids.
17. a crucible.
- Heating solids for use.
18. A small amount of solid reagent --- the surface dish.
19. The burning spoon --- used when the solid is burned.
20. The test tube brush --- used when washing the test tube or flask.
Glass instruments that cannot be used for heating: measuring cylinders, gas collection cylinders, funnels, thermometers, dropper bottles, surface dishes, jars, fine-mouth bottles, etc.
It can directly heat instruments: test tubes, evaporation dishes, crucibles, burning spoons.
Can not be heated directly (pad with asbestos nets.
Beakers, flasks, Erlenmeyer flasks.
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Anonymous users2024-02-12The commonly used equipment in the chemistry laboratory is:
1. Beaker: A beaker refers to a common laboratory glassware, made of glass, plastic, or heat-resistant glass. The beaker is cylindrical in shape and has a notch on one side of the top for easy pouring of liquids.
Beakers are widely used for heating, dissolving, mixing, boiling, melting, evaporating concentration, dilution, precipitation and clarification of chemical reagents.
2. Graduated cylinder: A graduated cylinder is an instrument for measuring the volume of liquid. The specifications are expressed in terms of the maximum capacity (ml) of the energy capacity, and the commonly used ones are 10 ml, 25 ml, 50 ml, 100 ml, 250 ml, 500 ml, 1000 ml, etc.
The scales on the outer wall are in ml, with a 10 ml cylinder representing ml per compartment and a 50 mL cylinder representing 1 mL per compartment.
3. Test tube: test tube, a commonly used instrument in chemical laboratories, used as a reaction vessel for a small amount of reagents, at room temperature or when heated (it should be preheated before heating, otherwise the test tube is easy to burst.) ) use.
There are many types of test tubes, such as ordinary test tubes, supported test tubes, and centrifugal test tubes. The specifications of ordinary test tubes are expressed in outer diameter (mm) and length (mm), such as 200, etc.
4. Alcohol lamp: Alcohol lamp is a heating tool fueled by alcohol, which is widely used in laboratories, factories, medical treatment, scientific research, etc. Since it does not produce smoke during combustion, it can also be sterilized by burning the instrument.
Due to the heat generated during the combustion of the alcohol lamp, other experimental materials can be heated. Its heating temperature reaches 400-1000 or more.
5. Burette: Burette refers to a measuring device that holds the titrant solution in the titration operation. The burette is a slender, uniform inner diameter and graduated glass tube, the lower end of the tube has a glass tip and has different volumes such as 25ml and 50ml.
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Anonymous users2024-02-11The names and uses of chemical laboratory equipment are as follows:
1. Test tube: used as a reaction vessel for a small amount of reagents at room temperature or heating conditions, collecting a small amount of gas and gas purification, and holding a small amount of drugs;
2. Evaporation dish: evaporation, concentration, crystallization of solution, drying and solidifying the repentant substance;
3. Crucible: used for high-temperature burning of solid substances;
4. Beaker: used as a container for dissolving solid substances and diluting liquids, as a container for the reaction of a large amount of reagents, for filtration, dialysis, fountain and other experiments, for air tightness testing, pre-tail gas absorption device, water bath heating, etc.;
5. Erlenmeyer flask: It can be used as a reactor for neutralization and titration, instead of test tubes, flasks, etc., as a reaction digger for gas generation;
6. Jar: used to store solid drugs, and can also be used to assemble gas generators;
7. Fine-mouthed bottles: used to store liquid medicines;
8. Measuring cylinder: roughly measure the volume of liquid, and measure the volume of solid and gas by measuring the volume of liquid;
9. Burette: accurately measure a certain volume of liquid, and measure the volume of the solution during neutralization and titration;
10. Volumetric flask: prepare a solution with a certain volume and accurate concentration.
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Anonymous users2024-02-10The names and uses of chemical laboratory equipment are as follows:
1. Test tube: used as a reaction vessel for a small amount of reagents at room temperature or heating conditions, collecting a small amount of gas and gas purification, and holding a small amount of drugs;
2. Evaporation dish: evaporation, concentration, crystallization of solution, drying of solid substances;
3. Crucible: used for high-temperature burning of solid substances;
4. Beaker: used as a container for dissolving solid substances and diluting liquids, as a container for the reaction of a large amount of reagents, for filtration, dialysis, fountain and other experiments, for air tightness testing, exhaust gas absorption device, water bath heating, etc.;
5. Erlenmeyer flask: It can be used as a reactor for neutralization and titration, instead of test tubes, flasks, etc. as a reactor for gas generation;
6. Jar: If the letter is used to store solid drugs, it can also be used to assemble a gas generator;
7. Fine-mouthed bottles: used to store liquid medicines;
8. Measuring cylinder: roughly measure the volume of liquid, and measure the volume of solid and gas by measuring the volume of liquid;
9. Burette: accurately measure a certain volume of liquid, and measure the volume of the solution during neutralization and titration;
10. Sliding volumetric flask: prepare a solution with a certain volume and accurate concentration.
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