52 A
ANALYTICAL
CHEMISTRY
HOW TO CHELATE ( p r o n o u n c e d "Key-late")
LUMETRON Colorimeter Mod. 450 for
Nessler Tubes
A new photoelectric instrument of high accuracy (or the measurement of pale colors and faint turbidities. * For all analytical colorimetric determinations in which only a slight coloration can be developed. * For sanitary examination of drinkable water and for analysis of water for municipal and industrial purposes. * For color standardization of lightly colored liquids such as kerosenes, sugar solutions, solvents, varnishes, liquid waxes, vegetable oils, beverages, cosmetics.
...Versene*
* Replaces visual color comparison in Nessler tubes. Write for literature to
PH0T0V0LT CORP.
VERSENE* CHELATES CATIONS
95 Madison A v e .
Before you can chelate foreign metallic ions in solutions you must have a powerful chelating agent such as Versene. This is a compound that will inactivate cations with the formation of inner ring structures in the molecule. It makes the metallic ion become part of the rings. This is a valuable thing to k n o w because it will prevent all kinds of contamination caused by cations.
PREFERENTIAL
Paper
Partition
CHROMATOGRAPHY
CHELATION
Equipment
When Versene is added t o a mixture of various metallic ions chelation will be preferential. That is, one metal will be complexed before another. When the first is exhausted the second will be inactivated and the process will g o o n until either metallic ions o r Versene are used up. Page 7 of Section I of Bersworth's Technical Bulletin N o . 2 gives a table which shows the order of chelation of some of t h e common metals at various pH's. Send for it.
VERSENES*—POWERFUL
New York 1 6 , Ν . Y .
A new and more complete line of paper chromatographic equip ment, carefully engineered for use in this new field of analysis. A CHROMATOGRAPHY V J D R Y I N G OVEN
CHELATING AGENTS
T h e Versenes, made only by the Bersworth Chemical Company under processes originated, developed a n d patented by F. C. Bersworth, are the most powerful chelat ing agents known. They are exceptionally stable at high temperatures and all pH's. Quality standards of manufac ture are so high that uniform complexing power is guar anteed for either sample o r carload quantities. Ask for TechnicalBulletin#2.WriteDept. V for samples. Chemical counsel available.
Also Available; • New Ghromatocab Models • Strip Suspension Racks (stainlesst steel or glass) • Electronic
Densitometers
• Ultraviolet Lamps (long and short wave-length) • Indicator Sprays
V E R S E N E * W A T E R T E S T K I T . Tells T o l o l Hordness In 2 minutes. Accurate f o 1 p e r g a l . Versenate method. Complete with instructions $ 5 . 0 0 Postpaid. T r a d e M a r k Registered "CHEMISTRY'S
MOST PRECISE
flrain
• Disc Chambers • Solvent Troughs semblies
CHCMICALS"
& As
• Micro Pipets
BERSWORTH CHEMICAL CO. FRAMINGHAM, MASSACHUSETTS Warehouse Stocks G e o r g e Mann & C o . , Inc. - Providence, R. I. · W a s a t c h Chemical C o . - Salt Lake C ' y G r i f f i n Chemical Co. - San Francisco - Los Angeles · K r a f t Chemical C o . - Chicago Siegel Chemical C o . - Brooklyn, N . Y .
·
C . S. Tanner C o . - Charlotte, N . C .
• Clips
Write for Catalog
RESEARCH
Copyright
1 9 5 2 , Bersworth
Chemical
Company
EQUIPMENT
CORPORATION
Manufacturers
B a r a d a & Page, Inc. Dallas - Houston - N e w Orleans - Oklahoma City - St. Louis - Tulsa - Wichita 1135
Third
Street
Dept. A
Oakland 20, California
