Model 5:'; :j ή jttHf Meter /

• A low-priced general-purpose instrument for educational or industrial laboratorv use

m Solid-state stability and reliability

CORNING pH METER, Model 5. A general utility instrument with an accuracy of ±0 .1 pH*. Line-operated; all solid state circuitry. Dual meter scale covers 0 to 14 pH and reads also from 0 to =1=700 mv. Reproducible within ±0.05 pH.

Jacks are provided for polarizing jumper for Karl Fischer titrations and for automatic tem­perature compensator, both available as acces­sories. Recorder jack is also provided. Shorting strap is not required. Meter. Taut-band movement. Scale length 5 ^ inches, graduated 0 to 14 pH in 0.1 pH divi­sions, and —700 to +700 mv in 10 mv. Mirrored to eliminate parallax. Panel Controls. Temperature compensation dial is scaled from 0° to 100°C in 2° divisions. Function switch has standby, pH, mv, and automatic temperature compensator positions. Calibration potentiometer is used for buffer standardization, asymmetry potential adjust­ment, and zeroing. *Accuracy obtained with error-free technique on samples within 4 pH units of standardizing buffer.

Polarizing Current. Twelve microamperes, for end point determination in Karl Fischer and similar procedures. Recorder Output. Ten millivolts, correspond­ing to full scale meter deflection. Grounding. Measurements can be made on grounded or ungrounded samples. Housing. Plastic, resistant to impact and chemical attack. Hinged, stainless steel stand provides adjustable viewing angle; elevates in­strument above bench spills. Overall dimen­sions 123/2 inches wide X 434 inches deep X 9 Κ inches high (to top of electrode support rod). Electrodes. Size 53^ inches long X 3^2-inch diameter, with 30-inch leads. Both cover range 0 to 14 pH, 10 to 80°C. Reference electrode is Ag-AgCl type with ceramic junction. 4875-C65. pH Meter, Model 5 (Coming 475000), as described. Includes 4876-J10 Glass Electrode, 4876-T10 Reference Electrode, electrode holder, electrode support rod, vial of pH 7.00 buffer powder to make 500 ml, and instruction manual. With 3-wire cord and plug, for 115 volts, 50 or 60 cycles, a.c. ; 3 watts. Can be converted for 230-volt operation in the laboratory. Without polariz­ing jumper or automatic temperature compensator 215.00

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Detailed literature sent upon request.

ARTHUR H. THOMAS COMPANY Scientific Apparatus and Reagents

V I N E S T R E E T AT 3 R D · P . O . B O X 7 7 9 · P H I U A D E L P H I A S , P A . , U . S . A .

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Corning