Care Should Be Taken When Using Volumetric Flasks

Check the tightness. After reversing the volumetric flask, observe whether there is water leakage, and then rotate the cork 180 degrees to observe whether there is water leakage. (1) the solute cannot be dissolved in the volumetric flask. The solute should be dissolved in the beaker and transferred to the volumetric flask. (2) The total amount of solvent used to wash the beaker shall not exceed the marking of the volumetric flask. Once it exceeds the marking, it must be reconstituted. (3) The volumetric flask cannot be heated. If the solute releases heat during the dissolution process, it shall be transferred after the solution is cooled. Because the temperature rises, the bottle and liquid will expand, and the volume measured will be inaccurate due to different expansion coefficients. (4) The volumetric flask can only be used to prepare the solution, and the solution cannot be stored for a long time or a long time, because the solution may corrode the bottle body, thus affecting the accuracy of the volumetric flask. (5) After the volumetric flask is used, it shall be washed in time, the cork shall be plugged, and a piece of paper shall be sandwiched between the cork and the bottle mouth to prevent adhesion between the cork and the bottle mouth. (6) The volumetric flask can only prepare a certain volume of solution, but generally retain 4 significant digits (e.g. 250.0ml). The number after the decimal point cannot be estimated because the solution exceeds or does not reach the scale line. It can only be reconfigured. Therefore, when writing the solution volume, it must be XXX 0mL[1]。