Cylinder, graduated

Graduated cylinders are generally not used for high-quality volumetric work. Although they are available in Class A, Class B, and Student Grade, the acceptable tolerance of graduated cylinders is considerably greater than volumetric 

Because liquids cannot wet plastic walls, plastic cylinders can provide constant volume for both to deliver and to contain. However, they are only accurate to Class B tolerances and susceptible to chemical attack from organic solvents. Regardless of the quality, or construction design, graduated cylinders have no calibration lines at the section closest to the base because when the body is fused onto the base, the overall shape of the tube is distorted and accurate calibration on a production basis is not possible. This feature is equally applicable to graduated cylinders that use a plastic press-on foot. 

Pharmaceutical graduated cylinders, which can be identified by their non-vertical walls,f have poor accuracy. Their accuracy varies at any given inside wall diameter, even on the same flask. For instance, at regions where the inside diameter is between 21 and 25 mm, the accuracy is 0.4mL. However, at regions where the inside diameter is between 46 and 50 mm, the accuracy is 1.8 mL. 

To fill a to contain cylinder (Style 1, 2, or 3), the following procedure should be followed  

Carefully place the liquid to be measured into the flask using a pipette, 

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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. 

Preparing a solution of known concentration is perhaps the most common activity in any analytical lab. The method for measuring out the solute and solvent depend on the desired concentration units, and how exact the solution s concentration needs to be known. Pipets and volumetric flasks are used when a solution s concentration must be exact graduated cylinders, beakers, and reagent bottles suffice when concentrations need only be approximate. Two methods for preparing solutions are described in this section. 

To prepare the solution we use a graduated cylinder to transfer 80 mb of glacial acetic acid to a container that holds approximately 2 b, and we then add sufficient water to bring the solution to the desired volume. 

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. 

API Filtration. A filter press is used to determine the wall building characteristics of mud. The press consists of a cylindrical mud chamber made of materials resistant to strongly alkaline solutions. A filler paper is placed on the bottom of the chamber just above a suitable support. The filtration area is 7.1 ( 0.1) in.-. Below the support is a drain tube for discharging the filtrate into a graduate cylinder. The entire assembly is supported by a stand so that a 100-psi pressure can be applied to the mud sample in the chamber. At the end of the 30-min filtration time volume of filtrate is reported as API filtration in milliliters. To obtain correlative results, one thickness of the proper 9-cm filter paper, Whatman No. 50, S S No. 5765, or the equivalent, must be used. 

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. 

A third technique used a variable density column. The variable density column is obtained by mixing gently a dense liquid, generally bromoform (density = 2.85 g/ cm ) with a light solvent, for example trichlorethane in a graduated cylinder. Calibration density beads are placed in the column for calibration. Shale cuttings are introduced carefully. They float at a level corresponding to their density. 

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. 

The uncertainty depends on the nature of the measuring device. Eight mL of liquid can be measured with less uncertainty in the 10-mL graduated cylinder than in the 100-mL graduated cylinder. 

WEB A solid with an irregular shape and a mass of 11.33 g is added to a graduated cylinder filled with water (d = 1.00 g/mL) to the 35.0-mL mark. After the solid sinks to the bottom, the water level is read to be at the 42.3-mL mark. What is the density of the solid ... 

The most commonly used pieces of apparatus in titrimetric (volumetric) analysis are graduated flasks, burettes, and pipettes. Graduated cylinders and weight pipettes are less widely employed. Each of these will be described in turn. 

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).

Dissolve a sample containing 0.5 meq anion-active material with a ether carboxylic acid group in alcohol and neutralize with 0.5 N NaOH on phenol-phthalein. Transfer this solution to a 250-ml graduated flask with a stopper and make up to the mark with distilled water. Introduce into a 100-ml graduated cylinder with a stopper ... 

Add 3-4 ml CPC solution (-0.005 N in distilled water). After each addition of CPC turn the graduated cylinder upside down 10 times. Too vigorous shaking leads to the formation of a stable emulsion. Add as rapidly as possible more CPC until the red chloroform layer settles out rapidly and clearly. Continue titrating slowly until the two layers have the same color. 

A. 13 When a piece of metal of mass 1 12.32 g is dropped into a graduated cylinder containing 23.45 mL of water, the water level rises to 29.27 mL. What is the density of the metal (in grams per cubic centimeter) ... 

A sample of hydrogen chloride gas, HC1, is being collected by bubbling it through liquid benzene into a graduated cylinder. Assume that the molecules pictured as spheres show a representative sample of the mixture of HC1 and benzene vapor ( represents an HCl molecule and O a benzene molecule), (a) Use the figure to determine the mole fractions of HCl and benzene vapor in the gas inside the container, (b) What are the partial pressures of HCl and benzene in the container when the total pressure inside the container is 0.80 atm ... 

C02-0074. Mercury is an unusual metal in that it is a liquid at room temperature. The density of liquid mercury is 13.55 g/mL. The photo shows a sample of mercury in a graduated cylinder. How many atoms of mercury are in the sample ... 

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