Ph Values At Various Temperatures; Electrode Conditioning And Maintenance - Hanna Instruments HI 22 Series Instruction Manual

pH VALUES AT VARIOUS TEMPERATURES

Temperature has a significant effect on pH. The calibration
buffer solutions are effected by temperature changes to a lesser
degree than normal solutions.
For manual temperature calibration please refer to the fol-
lowing chart:
TEMP
°C
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
For instance, if the buffer temperature is 25°C, the display
should show pH 4.01, 7.01 or 10.01 at pH 4, 7 or 10
buffers, respectively.
At 20°C, the display should show pH 4.00, 7.03 or 10.06.
The meter reading at 50°C will then be 4.06, 6.98 or 9.82.
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pH VALUES
°F 4.01 7.01 10.01
32 4.01 7.13 10.32
41 4.00 7.10 10.24
50 4.00 7.07 10.18
59 4.00 7.04 10.12
68 4.00 7.03 10.06
77 4.01 7.01 10.01
86 4.02 7.00 9.96
95 4.03 6.99 9.92
104 4.04 6.98 9.88
113 4.05 6.98 9.85
122 4.06 6.98 9.82
131 4.07 6.98 9.79
140 4.09 6.98 9.77
149 4.11 6.99 9.76
158 4.12 6.99 9.75

ELECTRODE CONDITIONING AND MAINTENANCE

* Only available with refillable electrodes. For industrial applications, gel-filled electrodes are preferable
due to lesser maintenance requirements.
PREPARATION
Remove the protective cap.
DO NOT BE ALARMED IF ANY SALT DEPOSITS ARE
PRESENT.
This is normal with electrodes and they will disappear when
rinsed with water.
During transport tiny bubbles of air may have formed inside
the glass bulb. The electrode cannot function properly under
these conditions. These bubbles can be removed by "shaking
down" the electrode as you would do with a glass thermom-
eter.
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