How to use laboratory test tubes correctly

Update:14-08-2020
Summary:

Laboratory test tubes can be directly heated. The speci […]

Laboratory test tubes can be directly heated. The specifications of test tubes are: test tubes are divided into ordinary test tubes, branched test tubes, centrifuged test tubes, etc.

To use test tubes correctly:

1. Use tweezers to take the block solid into the test tube. Do not drop the solid directly into the test tube to prevent the bottom of the test tube from breaking;

2. Do not exceed 1/2 of the test tube capacity when filling the solution, and not exceed 1/3 of the test tube when heating.

3. When using a dropper to drip liquid into the test tube, it cannot reach into the test tube mouth;

4. When using the test tube clamp to clamp the test tube, put the test tube clamp up from the bottom of the test tube and clamp it on the middle and upper part of the test tube. Within one part is reasonable.  

5. Heating application outer flame

 

 

6. After heating, it can not be quenched to prevent cracking.

7. Preheat when heating to prevent the test tube from bursting due to sudden heat.

8. When heating, keep the outer wall of the test tube free of water droplets to prevent uneven heating and bursting.

9. Do not wash the test tube before it has cooled to room temperature after heating.

10. Use the test tube clamp for heating, and the test tube mouth should not face people. When heating a test tube containing solids, the nozzle of the tube should be slightly downward, and the liquid should be tilted about 45° when heating the liquid; the test tube clamp should be clamped at 1/3 of the bottle opening.

11. Heat evenly to avoid bumping or bursting of test tubes;

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