16
I. pH Buffers
The temperature coefficient of pH calibration buffers 1.68, 4.00,
4.01, 6.86, 7.00, 9.18 , 10.01 and 12.46 pH are stored inside the
instrument. The buffers used to calibrate the instrument must
exhibit the same temperature characteristics as the stored
values.
Temperature coefficient of the pH buffers
°C
1.68 4.00 6.86 9.18 4.01 7.00 10.01 12.46
0
1.67
4.01
6.98
9.46
4.01
7.11
10.32 13.42
5
1.67
4.00
6.95
9.39
4.01
7.08
10.25 13.21
10
1.67
4.00
6.92
9.33
4.00
7.06
10.18 13.01
15
1.67
4.00
6.90
9.28
4.00
7.03
10.12 12.80
20
1.68
4.00
6.88
9.23
4.00
7.01
10.06 12.64
25
1.68 4.00 6.86 9.18 4.01 7.00 10.01 12.46
30
1.68
4.01
6.85
9.14
4.01
6.98
9.97
12.30
35
1.69
4.02
6.84
9.10
4.02
6.98
9.93
12.13
40
1.69
4.03
6.84
9.07
4.03
6.97
9.89
11.99
45
1.70
4.04
6.83
9.04
4.04
6.97
9.86
11.84
50
1.71
4.06
6.83
9.02
4.06
6.97
9.83
11.71
55
1.72
4.07
6.83
8.99
4.08
6.97
9.80
11.57
60
1.72
4.09
6.84
8.97
4.10
6.98
9.78
11.45
[Note:
The actual reading of the instrument can differ from the
values shown by
±
0.01 pH
]
J. Preparing Conductivity Standard Solutions
Suitable conductivity standards are available commercially or
the user can prepare them using research grade reagents.
Here are some standard solutions the user can prepare to
calibrate the probe of the model 6377.
1. Standard solution of 1413 uS/cm at 25
℃
: Accurately weight
out 0.746 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000 ml of distilled water.
2. Standard solution of 12.90 mS/cm at 25
℃
: Accurately weight
out 7.4365 grams of research grade dried Potassium Chloride
(KCL). Dissolve in 1000 ml of distilled water.
