The correct way to wash the tubes, what is the instrument that should be used to wash the tubes

First pour out the residual liquid in the test tube, add half the test tube water to shake, if it is difficult to wash off, you can use a test tube brush. Move up and down or gently turn the tube brush.

Do I have to clean the tube with a test tube brush? Is it okay to just rinse with water? "A lot of people have this question.

The answer is no. Because there may be excess liquid and chemical substances remaining in the test tube after the experiment, only rinsing with water may not be able to wash the substance off, and the residue is likely to affect the accuracy of the experiment in the future or even cause injury, so it is necessary to use a test tube brush to scrub off the residual substance.

Wash the tube after use.

Drain the waste liquid from the test tube first.

2. Inject half a test tube of water again, pour out the water after shaking, inject water again, pour it out again after shaking, and wash it several times.

3. If there is a substance attached to the inner wall that is not easy to wash off, it should be brushed with a test tube. When brushing, the tube brush must be rotated or moved up and down, but not too hard to prevent damage to the tube.

4. When the water attached to the inner wall of the washed glass instrument does not gather into droplets, nor does it flow down in strands, it means that the instrument has been cleaned. The washed glass instrument should be placed on a test tube rack or in a designated place.

Extended information: Do not exceed 1 2 of the volume of the test tube when filling the solution, and do not exceed 1 3 of the volume of the test tube when heating. [1]

2) When using a dropper to add liquid to the test tube, it should be suspended and not extended into the mouth of the test tube. [1]

3) Take the lumpy solid and use tweezers to pick it up and put it at the mouth of the test tube, and then slowly erect the test tube to make the solid slide into the bottom of the test tube, so that the solid can not fall directly into it to prevent the bottom of the test tube from rupturing. [1]

4) Use a test tube clamp for heating, and the mouth of the test tube should not be facing people. When heating a tube containing solids, the nozzle is slightly downwards and the liquid is heated at an angle of about 45°. [1]

5) The heating should be even, so as to avoid boiling or bursting of the test tube. [1]

6) Do not quench after heating to prevent breakage. [1]

7) Preheat when heating to prevent the test tube from bursting due to sudden heating. [1]

8) Keep the outer wall of the test tube free of water droplets when heating to prevent bursting due to uneven heating. [1]

9) After heating, do not wash the test tube before it has cooled to room temperature. [1]

10) When using the test tube clamp to clamp the test tube, the test tube clamp is sleeved from the bottom of the test tube to the top, clamped in the middle and upper part of the test tube, if the length of the test tube is divided into three, the test tube clamp is reasonable within one-third of the end of the test tube mouth. [1]

11) Heating application external flame. [1]

Depending on the surface tension of the liquid and the nature of the glass, the glass can be wetted with water. A drop of water placed on a clean glass plate will adhere to the glass plate to form a thin layer.

When a piece of clean glass is put into the water and then removed, the surface of the glass will be stained with a layer of water. If there are water droplets or streams down, it means that there is a substance on the surface of the glass that does not allow water to soak, which indirectly proves that the glass is not clean.

Precautions for the use of test tubes.

Remove the reagent cork, the reagent cork is placed with the big head down and the small head up to avoid corroding the tabletop, when pouring liquid into the test tube, the mouth of the reagent bottle is aligned and next to the mouth of the test tube, the test tube is slightly tilted, the label of the reagent bottle should be aligned with the palm of the hand to prevent the reagent from corroding the label, slowly pour in the liquid, after pouring the liquid, immediately cover the cork and put it back in place, the label should be placed outward, so that the experimenter can know the type of reagent.

Use the rubber tip dropper to add liquid to the test tube, the rubber tip dropper can not extend into the test tube, but should be placed above the mouth of the test tube and added vertically. Prevent contamination of the tip dropper and thus the reagent.

After the tube is cleaned, there will be water on the inner wall, and when the water on the inner wall of the tube does not collect into droplets or run down in strands, the tube is cleaned.

The instrument that should be used to wash the test tubes is the test tube brush. Test tube brush, also known as pipe brush, straw brush, hole cleaning brush, twisted wire brush, pipe brush, etc., is a very widely used Shiyuanqing brush product, mainly made of iron wire (steel wire) as the skeleton, with many neatly arranged, outward stretching fine brush filament.

The filament materials of the test tube brush include nylon wire, fiber wool, bristles, steel wire, copper wire, abrasive wire, etc., which have different scope of use. The test tube brush is mainly used to remove tiny burrs on the surface of the finished hole, thereby improving the finish of the inner hole.

Generally raised by one small level to one large level. According to the condition of the workpiece, test tube brushes of different materials should be selected, such as metal polishing pipe grooves, steel wire test tube brushes or copper wire test tube brushes can be selected. When using, the fracturing grip should not be too large, as excessive pressure will cause the thin wires on both sides to be distorted or overheated, resulting in the cracking and fracture of the fine wires, which will melt quickly and reduce the service life.

When cleaning glassware, it is generally necessary to pour out the dirt first, then rinse with tap water, brush with washing liquid, then rinse with tap water, and finally rinse with pure water (distilled or deionized water) three times. The inner wall of the container should be cleaned in such a way that the water is evenly moistened and free of water droplets.

Beakers, Erlenmeyer flasks, cuvettes, test tubes, etc., commonly used in the laboratory, can be washed with detergents and brushes according to the above methods.

Burettes, pipettes, pipettes, volumetric flasks, graduated cylinders and other glass instruments with precision scales should not be brushed to avoid hurting the scale marks, and it is best to use y eadar

Cleaning and disinfection machine for laboratory, special cleaning agent and cleaning program for spray rinsing and blow drying. Alternatively, soak in synthetic detergent or chromium pickling solution for a period of time before rinsing off.

Glass instruments such as cuvettes made of optical glass should not be brushed with a brush, and when soaking with lotion liquid, it is also necessary to prevent the problem of decreasing light transmittance caused by infiltration caused by long-term soaking. Because cuvettes are usually chromogenic reactions, it is recommended to soak them in a synthetic detergent or hydrochloric acid-ethanol solution for a few minutes before rinsing them off. Or use a special cleaning and disinfection machine for laboratory cleaning, special cleaning agent and cleaning program for spray rinsing and blow drying.

When washing glassware, it should comply with the principle of small quantities and many times, which is economical and improves efficiency. Do not wipe the cleaned container with a cloth or filter paper, as this will leave fibers or dirt on the utensils and contaminate the container. When drying, either use upside down hanging drying, or use a drying oven (if the solvent is used for the final rinse, do not put it in the drying oven to avoid danger).

Depending on the dirt on the test tube, different solvents are used to wash the dirt, alkali is used for alkaline soil, alkali is used for acidic soil, organic solvent is used for organic soil, and water is generally used for washing.

Brush with a test tube; Or tilt the tube to pour water into it and wash the tube left and right!

The oil on the tubes is washed with a hot NaOH solution or a Na2CO3 solution (the oil is hydrolyzed under a strong alkaline solution).

There is a solution of hot NaOH on the tube (principle: 3S + 6NaOH = heating = 2Na2S + Na2SO3 + 3H2O).

There is a silver mirror on the test tube with dilute Hno3 solution (principle: 3AG + 4HNO3 (dilute) = 3AGnO3 + NO( )2H2O).

There is dilute hydrochloric acid (principle: Cuo + 2HCl = CuCl2 + H2O) on the test tube

Too much to write. Good luck with your studies!!

Carbon disulfide can also be used to remove NaOH from sulfur washing.

The instrument shed jujube device commonly used in the laboratory to wash test tubes is a test tube brush; When the water on the inner wall of the washed glass instrument does not gather into droplets or flow down in strands, it means that it has been cleaned

So the answer is: test tube brush; When the water attached to the inner wall of the test tube does not gather into droplets or flow down in strands, it means that the test tube has been cleaned