Bottle standards

Label a clean 250-mL plastic bottle Standard NaOH Solution. Write your name and the date of preparation on the label. 

Sodium Hydroxide, 1N (40.00 g NaOH per 1000 mL) Dissolve about 40 g of sodium hydroxide (NaOH) in about 1000 mL of carbon dioxide-free water. Shake the mixture thoroughly, and allow it to stand overnight in a stoppered bottle. Standardize the clear liquid as follows Transfer about 5 g of primary standard potassium biphthalate [ KHCgH4(COO )2], previously dried at 105° for 2 h and accurately weighed, to a flask, and dissolve it in 75 mL of carbon dioxide-free water. If the potassium biphthalate is in the form of large crystals, cmsh it before drying. To the flask add 2 drops of Phenolphthalein TS, and titrate with the sodium hydroxide solution to a permanent pink color. Calculate the normality. Each 204.2 mg of potassium biphthalate is equivalent to 1 mL of 1 N Sodium Hydroxide. 

Environmental agencies, as well as others studying pollution in the nation s waterways, need materials containing an accurate composition of various compounds as a check to verify the reliability of laboratory instruments and methods. The National Institute of Standards and Technology (NIST) has developed a bottle standard marine reference material (SRM) for this purpose. It contains marine sediment with a wide range of pollutant compounds of interest to environmental scientists. The sediment material, which has certified values of 11 polycyclic aromatic hydrocarbons (PAHS), was collected from the Chesapeake Bay area near Baltimore harbor. It is a dry powder that can be reconstituted into a wet form so that the compounds can be extracted by solvents for organic analysis. See environment. 

The ultramarines range in color from a medium shade blue through violet to pink. A household example of an ultramarine blue in full shade is the Milk of Magnesia bottle. Standard grades of ultramarine pigments (uncoated) react with polyacetal resins, and I have observed color drift of these pigments in PC and PA 6/6. Some properties of ultramarine pigments are listed in Table 1. 

Determination of Turbidity between 25-100 JTU with Bottle Standards... 

To determine the exact perbenzoic acid content of the solution, proceed as follows. Dissolve 1 -5 g. of sodium iodide in 50 ml. of water in a 250 ml. reagent bottle and add about 5 ml. of glacial acetic acid and 5 ml. of chloroform. Introduce a known weight or volume of the chloroform solution of perbenzoic acid and shake vigorously. Titrate the liberated iodine with standard O lA sodium thiosulphate solution in the usual manner. 

Samples of car exhaust are collected using a 4-L glass bottle evacuated to a level of less than 2 torr. A normal calibration curve using external standards of known Pco is used to determine the Pco in the exhaust samples. 

Fat Content of Milk. Raw milk as well as many dairy products are routinely analyzed for their fat content. The Babcock test, or one of its modifications, has been a standard direct measure for many years and is being replaced by indirect means, particularly for production operations. The Babcock test employs a bottle with an extended and caHbrated neck, milk plus sulfuric acid [7664-93-9] to digest the protein, and a centrifuge to concentrate the fat into the caHbrated neck. The percentage of fat in the milk is read direcflv from the neck of the bottle with a divider or caHper, rea ding to... 

Statistical control of an analysis or instmment is best demonstrated by SQC of a standard sample analysis. The preferred approach to demonstrate statistical control is to use a reference sample of the subject material that has been carefully analyzed or, alternatively, to use a purchased reference standard. Either material must be stored so that it remains unchanged, eg, sealed in ampuls or septum capped bottles. Periodically a sample can then be reanalyzed by the technique used for routine analysis. These results are plotted in a control chart. Any change in the stabihty of the test in question results in a lack of... 

When you pour boiling water into a cold bottle and discover that the bottom drops out with a smart pop, you have re-invented the standard test for thermal shock resistance. Fracture caused by sudden changes in temperature is a problem with ceramics. But while some (like ordinary glass) will only take a temperature "shock" of 80°C before they break, others (like silicon nitride) will stand a sudden change of 500°C, and this is enough to fit them for use in environments as violent as an internal combustion engine. 

Due consideration of these principles has made it possible to process unplasticised PVC by all the standard melt processes, including injection moulding and bottle blowing, a state of affairs hardly conceivable in the 1950s. 

At the conclusion of the reaction, the excess hydrogen is vented, the bottle is removed, and the bulk of the catalyst is recovered by filtration. In practice, the catalyst is so finely divided that a second filtration through celite is often necessary to give a pure filtrate. The solvent is then removed and the residue is worked up by standard procedures. 

It is rarely that any greater degree of accuracy than that attained in the above methods is required. If, however, scientific accuracy is necessary in specific gravity determinations, the usual standard of comparison, at whatever temperature the determination may be made, is water at its maximum density temperature, namely 4°. If no correction is made for the weight of the air contained in the bottle or tube, accuracy to the fourth place of decimals is ensured by reducing the observed weighings to vacuum weighings. This can be done by the equation—... 

Stand-kugel, /. stationary bulb, -morser, m. a heavy mortar with a firm base, -dl, n. stand oil, lithographic oil (made by heating linseed oil), -ort, m. n. station, stand location, site (Sot.) habitat, -punkt, m. standpoint standard, -rohr, n. standpipe, vertical pipe, -sicherheit, /. stability, -tropfglas, n. dropping bottle. -verlust, m. storage loss. -wa(a)ge,/. platform balance or scales, -zy-linder, m. a standing cylindrical vessel, cylinder,... 

Titrier-flasche,/. titration bottle (for feeding a buret), -fliissigkeit, /. titrating solution, standard solution, -gerate, n.pl. titrating apparatus, -methode, /. titration method, volumetric method, -saure, /. titrating acid, standard acid. 

Marsh Funnel. The funnel is dimensioned so that, by following standard procedures, the outflow time of 1 qt (946 ml) of freshwater at a temperature of 70 5°F is 26+0.5 seconds [23]. A graduated cup or 1-qt bottle is used as a receiver. 

---