The view sight is going through two layers of glass and liquid, if the liquid is turbid, the scale is even less visible, and the scale figures are not pleasing to the eye.
So the scale should face the user. After injecting the liquid, wait for 1 to 2 minutes to allow the adhering liquid to flow down the inner wall, and then read the scale value. Otherwise, the value read is smaller than actual value. Place the graduated cylinder on a flat surface first and then view the height of the liquid in the cylinder with your eyes directly. Always look straight from the side of the meniscus at the graduated cylinder to measure and never try to read from above or below.
Otherwise, the value will be higher or lower than the actual value. As the temperature rises, the cylinder expands and the volume increases. So,unlike the glass test tubes, measuring cylinder can not be heated, nor can it be used to measure the superheated liquid, and it is impossible to carry out chemical reaction or formulate the solution in the measuring cylinder.
This depends on the specific situation. If it is only for the measurement to be accurate, it is not necessary to flush the cylinder with water, since the residual liquid is already taken into account when manufacturing the cylinder. Conversely, if flushing, the volume taken will be higher than actual value.
If you want to use the same cylinder to measure other liquids, you must flush it with water to prevent contamination. For example, the lowest scale is 1mL for the 10mL cylinder and the lowest for the mL cylinder is 50mL.
Luckily, there is a straightforward way to calculate the volume of irregular objects by measuring the water levels in a graduated cylinder. Water-insoluble Object:. Choose a graduated cylinder which the object can easily fit inside,add water to the measuring cylinder,read the initial water level V1.
Tilt the cylinder to slide the object into the water slightly,make sure the object is completely submerged in the water,note down the final water level V2. The volume of the irregular object V can be obtained by subtracting the volume of the first volume V1 from the final volume V2,ie. Note: If the density of the object is less than the water and floating in the water, you can press it into the water with a fine needle, such as a wooden block.
Water-soluble Object:. If the object is soluble in water, you can put fine sand in the measuring cylinder, shake the surface and smooth it out to read V1, then bury the small object in the fine sand and shake it evenly to read V2. Do not use a brush to clean the measuring cylinder,wash it continuously with water,then flush with distilled water. The graduated cylinder should be kept in dry and safe place in case of damage or pollution,such as laboratory cabinet.
Measuring cylinder is an essential and economical measuring device for laboratory,kitchen and many other laboratory occasions. The measuring cylinder can only be used when the precision requirement is not very strict. It is usually used in qualitative analysis and is generally not used for quantitative analysis because the error of the measuring cylinder is big. Why is a graduated cylinder used to measure volume?
Graduated Cylinders and Beakers are both common pieces of laboratory equipment. A Graduated Cylinder has a narrow cylindrical shape with each marked line showing the volume of liquid being measured. The Beaker's main function is stirring, mixing and heating liquids.
What determines which glassware you measure with? Graduated cylinders, beakers, volumetric pipets, burets and volumetric flasks are five kinds of glassware often used to measure out specific volumes. Volumetric pipets, flasks and burets are the most accurate; the glassware makers calibrate these to a high level of accuracy. Why is it called graduated cylinder? Graduated Cylinder. As its name indicates, it is a glass cylinder with marks along the side similar to those on a measuring cup.
The volume is read by looking at the top of the fluid from the side and reading the mark on the glass from the lowest portion of the lens-like meniscus of the liquid. Is percent error a measure of accuracy or precision? The accuracy is a measure of the degree of closeness of a measured or calculated value to its actual value.
The percent error is the ratio of the error to the actual value multiplied by The precision of a measurement is a measure of the reproducibility of a set of measurements. Why is pipette more accurate than measuring cylinder? They are inaccurate because of the large meniscus. Graduated Cylinders: A graduated cylinder is a quick and easy though less accurate way to measure the volume of a liquid.
Volumetric pipets are so accurate because the long neck decreases the error in measuring volume of the meniscus. What is the difference between a beaker and a measuring cylinder? Both graduated cylinders and beakers are pieces of laboratory glassware that have a specific function. Graduated cylinders typically are more accurate at reading the volumes of the liquid inside.
Beakers are better for stirring and mixing liquids. What are the sizes of beakers? How precise is a graduated cylinder? The smallest division of this graduated cylinder is 1 mL. Therefore, our reading error will be 0. An appropriate reading of the volume is An equally precise value would be What is a burette used for? Burette, also spelled Buret, laboratory apparatus used in quantitative chemical analysis to measure the volume of a liquid or a gas.
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