Volume measurement graduated cylinders

Scientists measure liquid volume in graduated cylinders that are marked with the units milliliter and liter. 

Common laboratory equipment used for the measurement of volume. Graduated cylinders (a), pipets (b), and burets (c) are used for the delivery of liquids volumetric flasks (d) are used to contain a specific volume. A graduated cylinder is usually used for measurement of approximate volumes it is less accurate and precise than either pipets or burets. 

Analytical chemists use a variety of glassware to measure volume, several examples of which are shown in Figure 2.4. The type of glassware used depends on how exact the volume needs to be. Beakers, dropping pipets, and graduated cylinders are used to measure volumes approximately, typically with errors of several percent. 

Calculate the molar concentration of NaCl, to the correct number of significant figures, if 1.917 g of NaCl is placed in a beaker and dissolved in 50 mF of water measured with a graduated cylinder. This solution is quantitatively transferred to a 250-mF volumetric flask and diluted to volume. Calculate the concentration of this second solution to the correct number of significant figures. 

A standard solution of Mn + was prepared by dissolving 0.250 g of Mn in 10 ml of concentrated HNO3 (measured with a graduated cylinder). The resulting solution was quantitatively transferred to a 100-mL volumetric flask and diluted to volume with distilled water. A 10-mL aliquot of the solution was pipeted into a 500-mL volumetric flask and diluted to volume, (a) Express the concentration of Mn in parts per million, and estimate uncertainty by a propagation of uncertainty calculation, (b) Would the uncertainty in the solution s concentration be improved... 

Calculate the sample s volume by measuring the amount of water that it displaces. This can be done by adding water to a graduated cylinder, reading the volume, adding the object, and reading the new volume. The difference in volumes is equal to the object s volume. 

Liquids and Solids Content. A mud retort is used to determine the liquids and solids content of the drilling fluid. Mud is placed in a steel container and heated until the liquid components have been vaporized. The vapors are passed through a condenser and collected in a graduated cylinder, and the volume of liquids (water and oil) is measured. Solids, both suspended and dissolved, are determined by volume as a difference between mud in container and distillate in graduated cylinder. 

The device most commonly used to measure volume in general chemistry is the graduated cylinder. A pipet or buret (Figure 1.8) is used when greater accuracy is required. A pipet is calibrated to deliver a fixed volume of liquid—for example, 25.00 mL—when filled to the mark and allowed to drain. Variable volumes can be delivered accurately by a buret, perhaps to 0.01 mL. 

Figure 18. Procedure for EPV (effective pore volume) measurement (a) a 50 g MnO, sample is placed in a 100 mL graduated cylinder (2) water is added gradually in 0.5 mL portions (3) with a stopper in place, the cylinder is turned upside down 10 times while being shaken (4) the cylinder is droppes 4 cm onto a wooden surface (5) the Mn02 sample volume is read after 5 and 10 taps (i.e., drops).

During an analytical cleanup run, the flow-rate must be 5.0 mL min. To check the flow-rate, measure the volume of the eluate in a graduated cylinder. 

The volume of water in the bottle is equal to the change in volume of the air as it cooled from the temperature of boiling water to the temperature of tap water. Use a graduated cylinder to accurately measure the volume of the water in the bottle. 

Using a clean 50-mL graduated cylinder, measure 25 mL of a solution of adipoyl chloride in cyclohexane and pour it into a 150-mL beaker. Record the volume used in Data Table 2. 

Sediment volume The sample used for measurements of settling rate was allowed to subside overnight for 16 to 24 hours and the sediment volume was read on the graduated cylinder. 

The most common method for measuring bulk density is to pour the powder into a tared graduated cylinder and measure the bulk volume (Vb) and mass of the material. Other methods, however, have been employed to ensure reproducibility, and a standard procedure has been reported [62,64]. For this testing, a sample of 50 g is passed through a U.S. Standard No. 20 sieve and is poured into a 100-ml graduated cylinder. The cylinder is then dropped from a height of 1 inch onto a hard surface three times at 2-second intervals. The volume of the powder is then read and used to calculate the bulk density. This three-tap method was found to give consistent results between laboratories. 

Tap density (ptap) is an extension of bulk density measurements, and the procedure used to measure the tap density again varies from lab to lab and can affect the final results. To measure tap density, a graduated cylinder is filled with powder and the weight and volume are recorded. The difference observed between procedures is the number of taps used for the measurement. In some cases, a particular number of taps is used, such as 200 [65], 500 [66], or even 1000 taps [67]. Other procedures involve tapping the cylinder for a number of times, recording the volume, and repeating the procedure until the volume remains constant [68]. This method ensures more consistent results. 

Epoxidation using a chiral fructose-derived ketone is easy to carry out, as it occurs in aqueous conditions. The reactions were performed without any modification of the published procedure. The glassware has to be free of trace metal, which can decompose the oxone the use of a plastic spatula is recommended and the volumes must be measured using glass-graduated cylinders. Table 6.2 gives different examples of epoxides which can be obtained using the method prescribed. 

Whether the volume measurements are for preparing solutions to be used in such a procedure, for transferring an appropriate volume of solution or solvent for such an analysis, etc., they need not be accurate since the outcome will be either only qualitative or not necessarily accurate. Such volumes should, however, be measured with other marked glassware, such as graduated cylinders or marked beakers and flasks. 

Prepare 1 L of 0.10 MHC1 by diluting the appropriate volume of concentrated HCl (12.0 M). Use a 1-L glass bottle and fill half of it with water before adding the concentrated acid. Use a graduated cylinder to measure the acid. Add more water to have about 1 L, shake well, and label. 

The density of an irregularly shaped solid is usually determined by measuring the mass and then measuring the volume of liquid that it displaces. The volume of liquid in a graduated cylinder is measured before the object is submerged and then measured again with the object submerged. The difference in the volume equals the volume of the object. 

To determine the density of a liquid, the mass in grams of a measured volume of liquid in milliliters is determined. The density is calculated from these measurements. The volume may be measured by a variety of devices, such as a graduated cylinder, pipet, or buret. Very precise determinations of volume are measured with pycnometers. These devices hold a specified volume. A cap or stopper with a capillary overflow tube ensures repeatability in the measurement. See Figure 15.15. 

Some tests, like lather volume, involved objective laboratory measurements. For example, a technician might produce lather by a prescribed washing procedure intended to consistently reproduce the same motions, and this lather volume would be measured in a graduated cylinder to give an objective measure [12], Other tests, like wet bar feel, required the subjective measurement of trained assessors. For example, the wet feel of a bar would be subjectively characterized as draggy or slippery by an expert panel of evaluators [13]. 

The two particular volumetric apparatus meant to contain a definite volume of liquid are volumetric flasks (also known as measuring or graduated flasks) and measuring cylinders (also known as graduated cylinders) which will be discussed here briefly ... 

Add about 15 mL of water to your graduated cylinder. Measure and record the volume. Because the surface of the water in the cylinder is curved, make volume readings at eye level and at the lowest point on the curve. The curved surface is called a meniscus. 

Use a graduated cylinder to measure 100 mL of distilled water. Very slowly, add the water to the beaker. Stop frequently to observe what happens. Keep track of how much water you add, and stop when no more water can be absorbed. (You may need to add less or more than 100 mL.) Record the volume of water at which the powder becomes saturated and will no longer absorb water. 

Place 500 ml of water in a 1 L volumetric flask. Carefully measure 21 ml of cone, hydrochloric acid in a 25 ml graduated cylinder and add to the flask. Rinse the cylinder with water and add the washings to the flask. Mix, dilute to volume and mix again. Add 0.5 ml of Brij 35 and mix thoroughly. 

The amount of acetylene is approximated by assuming a density of 0.7 g/mL. Approximately 2.5-3.0 equiv of acetylene is used. THF is added to the graduated cylinder so that the final volume of the acetylene solution will be 100 mL. In this case, 30 iii. of acetylene is measured to provide approximately 0.85 mol. 

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