[China Glass Net] The test tube can be directly heated, and the size of the glass test tube is divided into: the test tube is divided into a common test tube, a test tube, a centrifuge tube, and the like.
To use the test tube correctly:
1. Take the block solid into the test tube and use the tweezers. Do not let the solid fall directly into the test tube to prevent the bottom of the test tube from rupturing.
2. Do not exceed 1/2 of the tube volume when loading the solution. Do not exceed 1/3 of the tube when heating.
3. When the liquid is dripped into the test tube with a dropper, it cannot protrude into the test tube.
4. When using the test tube clamp to take the test tube, set the test tube clamp from the bottom of the test tube to the upper part of the test tube and clamp it in the upper part of the test tube. If the length of the test tube is three equal parts, the test tube clamp is clamped at the end of the test tube. It is reasonable to have a part within one.
5. Heating the outer flame.
6, can not be quenched after heating to prevent cracking.
7. Preheat when heating to prevent the tube from bursting and bursting.
8. When heating, keep the outer wall of the test tube free of water droplets to prevent the heat from being uneven and burst.
9. After heating, the test tube should not be washed when the test tube is not cooled to room temperature.
10, heating using the test tube holder, the test tube mouth can not be facing people. When heating a test tube containing solids, the nozzle is slightly downward, and the liquid is tilted by about 45° when the liquid is heated; the test tube holder should be clamped at 1/3 of the mouth of the bottle.
11, the heat should be even, so as not to bump or burst the test tube.
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