What Are Graduated Cylinders?

A graduated cylinder, measuring cylinder or graduated glass is a glass instrument used to measure liquid. A graduated cylinder is an instrument for measuring the volume of a liquid. The specifications are expressed in terms of the maximum capacity (mL) of the energy. Commonly used are 10 mL, 25 mL, 50 mL, 100 mL, 250 mL, 500 mL, 1000 mL, etc. The scale on the outer wall is in mL. A 10 mL graduated cylinder represents 0.2 mL per cell, and a 50 mL graduated cylinder represents 1 mL. It can be seen that the larger the measuring cylinder, the thicker the pipe diameter, the smaller its accuracy, and the larger the reading error caused by the deviation of the line of sight. Therefore, according to the volume of the solution taken in the experiment, try to use the smallest size measuring cylinder that can be measured at one time. Fractional measurements can also cause errors. For measuring 70ml of liquid, a 100mL graduated cylinder should be used.

Measuring cylinder is a kind of measuring instrument used in the laboratory, mainly used

1. How to fill the cylinder with liquid?

When injecting liquid into the vector cylinder, hold the measuring cylinder with your left hand to make the measuring cylinder slightly tilted, and hold the reagent bottle with your right hand so that

The measuring cylinder is a coarse measuring instrument with its accuracy. If the minimum scale of the measuring cylinder with a range of 5mL is 0.1mL, its accuracy is 0.1mL; if the minimum scale of the measuring cylinder with a range of 10mL is 0.2mL, its accuracy is 0.2mL; , Its accuracy is 1mL and so on. Common and more accurate measuring cylinders can only record a valid value after the decimal point ^[2]

1. Cannot be used as a reaction container

2. Can't heat

We like to dry in the oven after washing, but the measuring cylinder is glassware, which will be deformed by heating, which will affect its accuracy. Especially repeated long-term heating and high-temperature heating.

3. Do not dilute concentrated acids and bases

Especially corrosive liquids. In addition, although glass is an inert material, it is not inactive. Some strong acids and bases, especially strong bases, still corrode it. Therefore, measuring cylinders that have been stored or used for a long time are not accurate.

4. Cannot store medicine

A graduated cylinder is a measuring device, not a container, and is not suitable for storing liquids.

5. Heatless solution without energy

If you measure too hot or too cold liquid, it is not accurate.

6. Do not use decontamination powder to avoid scratching the scale

The measuring cylinder is not allowed to brush, because the scrubbing will wear the inner wall of the measuring cylinder, causing the content volume of the measuring cylinder to change, which will affect the accuracy of the measuring cylinder. But the graduated cylinders in a few more labs have not been brushed.

7 No need to rinse

Sometimes after we finished pouring, we found that there were a lot of hanging walls in the measuring cylinder. I felt that the amount was not enough, and we repeatedly rinsed with solvents or other means. In fact, this is also wrong, because the wall of the graduated cylinder was taken into consideration at the beginning of the design of the graduated cylinder. This volume is taken into account, and the volume poured out is the volume we need.