Precautions For Using Glass Test Tube

1. In order to facilitate shaking and prevent overflow outside the tube during boiling, the liquid drug contained in the glass test tube shall not exceed I / 3 of the volume.

2. The powdered drugs can be fed into the paper trough, and the granular drugs can slide down slowly along the inner wall of the glass test tube. They must not be dropped vertically to avoid breaking the bottom of the glass test tube.

3. The outer wall of the glass test tube shall be wiped dry before heating to prevent cracking due to uneven heating of the glass test tube.

4. The liquid shall be heated evenly, and the bottom of the heating glass test tube shall not be fixed to prevent the liquid from ejecting. When heating, the glass test tube should maintain a 45 ° angle with the experimental table, so that the liquid will have a large heating area and evaporation surface to keep the boiling uniform.

5. When heating, the nozzle is not for people, so as to prevent people from being injured by liquid splashing.

6. Solid heating shall be preheated first, and then fixed heating. In order to prevent the condensation water from flowing back to the hot bottom and causing cracking, the mouth of the glass test tube should be slightly downward.

7. The freshly burned glass test tube shall be placed on the asbestos net and allowed to cool slowly to avoid sudden cooling and cracking.