Datasheet
Measurement Engineering for Analysis
Information
22
Overview
Why You Should Choose Analysis Instruments from Testo
Analytical instruments are only as accurate as the sensor used. When measuring pH
only those probes suited to the particular substance can guarantee an accurate
reading.
Definition of the pH value
pH is the abbreviation of the Latin expression „pondus hydrogenii“ (pondus =
pressure, hydrogenium = hydrogen).
It is therefore a measure for the activity of the hydrogen ions in a substance. The
activity is connected directly to its acidic, neutral or alkaline character.
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Examples of the pH values of everyday substances
ACIDIC NEUTRAL ALKALINE
Stomach acids
Lemon juice
Sour milk,
yoghurt
Ion free water
Hard well water
Soap
Lime water
1M NaOH
pH electrodes / conductivity measurement sensors and their applications
Order no. 0650 2063
pH universal plastic electrode without temperature sensor
Order no. 0650 2064
pH universal plastic electrode with temperature sensor
Order no. 0650 1623
pH glass electrode with temperature sensor
Order no. 0650 0245
pH food electrode without temperature sensor
+ suitable 0 suitable in certain cases – not suitable
(Part no. 0650 2063) (Part no. 0650 1623) (Part no. 0650 0245) (Part no. 0650 2064)
Applications
Part-aqueous sol. >10% H
2
O
Part-aqueous sol.
<
10% H
2
O
pH measurements at temperatures up to 100 °C
TRIS buffer solutions
Effluent samples
General aqueous solutions
Aquariums
Beer, fruit juice, wine
Yoghurt, cheese
Substances containing protein
Emulsions, aqueous
Emulsions, part aqueous
Earth (suspension)
Extreme pH values (pH
〈
1, pH>13)
Penetration meas. in meat
Penetration meas. in fruit,veg
Substances with hydrofluoric acid
Galvanic sewage
Hot electrolyte
Highly viscous solutions
Infusion solutions
Solutions low in ions
Jams
Cosmetic products
Leather, paper
Milk
Pure and rain water
Cream, whipped yoghurt
Brine
Swimming pools
Soaps, detergents
Aqueous suspensions
Part-aqueous suspensions
Pastry, bread
+–
0–
–– –
0+ +
++ +
++ +
++ +
0+ 0
–+–
–0+–
+0
+–
0+ –
00 –
––+–
––+–
–– –
+–
–0 –
0–
+0
–0 0
–+–
0
0– –
+++
–+ 0
0+–
0+ +
++ +
+–
+–
+–
–+–
02-098X-709X-Measurement 13.12.2010 09:23 Seite 2