18 A A N A L Y T I C A L C H E M I S T R Y

A S C A R Ι Τ Ε (REGISTERED TRADE MARK)

(SODIUM HYDRATE ASBESTOS ABSORBENT)

BOTH MESHES NOW AVAILABLE FOR IMMEDIATE SHIPMENT

Since its introduction in 1918, Ascarite has become the uni­versally accepted standard C02 absorbent in the iron and steel industry.

Also widely used in quantitative organic microanalysis, and in the analysis of respiratory gases, etc.

ASCARITE (Registered Trade Mark), Sodium Hydrate Asbestos Absorbent. Prepared in accordance with the formula of the late James B. Stetser for the rapid and quantitative absorp­tion of C02 in the determination of carbon in iron and steel and in universal use for this purpose in the iron and steel industry; also used in carbon-hydrogen determinations, particularly in quantitative organic microanalysis, and in the analysis of respiratory gases, etc.

While originally designed for use in the Stetser-Norton modification of the Midvale Absorption Bulb, it can be used with equal satisfaction in the Johnson modification, and in the original Mid-vale, Vanier, Fleming, Nesbitt, Turner, Miller, and similar bulbs. Sixty grams of Ascarite (the contents of a Midvale Absorption Bulb) will absorb from 10 to 15 grams of C02. Therefore, 500 grams of Ascarite provides for from 2000 to 4-000 determinations.

Bibliography (For additional references, see page 399 of our catalogue.) J. B. Stetser and It. H. Norton, "Combustion Train for Carbon Determination," The Iron Age, Vol. 102, No. 8

(Aug. 22, 1918). J. B. Stetser, "Ascarite," Chemistry and Industry (London), Vol. 43, No. 25 (June 20, 1924), P- 637. A.S.T.M. (American Society for Testing Materials), "Methods for Chemical Analysis of Metals," 1950, p. β. Fritz Pregl, "Quantitative Organische Mikroanalyse," 5th ed. edited by H. Roth (Vienna, 1947). p. 18; and 5th

English ed., revised and edited by Julius Grant (Philadelphia, 1951 ) , p. 50. AI. Steyermark, "Quantitative Organic Microanalysis." (Philadelphia, 1951). p. 84, ff.

Mesh 8 to 20 20 to 30 Per 1 lb., in bottle with plastic screw cap 5.00 5.00 Code Word Vlvrf Vlxga

5 % discount in carton containing 12 X 1 lbs. 10% discount in lots of 48 lbs. ) , assorted meshe* 15% discount in lots of 144 lbs. f o n e m e s n o r a s s o r t e c l meshes

COLOR CHANGE. During use, the color of Ascarite, which is light brown in the original product, gradually turns to white due to the absorption of carbon dioxide and the formation of sodium carbonate. This color change occurs within a narrow zone and is clearly perceptible. Because of this marked difference in color between the used and unused portions of the absorbent, it is possible to determine when a bulb should be discarded.

ARTHUR H. THOMAS COMPANY LABORATORY APPARATUS AND REAGENTS

WEST WASHINGTON SQUARE PHILADELPHIA 5, PA.

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