4 stored buffer series, Stored buffer series – Metrohm 781 pH/Ion Meter User Manual
Page 160
9.4 Stored buffer series
150
780/781 pH/Ion Meter, Manual
9.4
Stored buffer series
For automatic buffer recognition during pH calibration the temperature-
dependent pH values of several common pH buffers are stored in the
780/781 pH/Ion Meter. Apart from the Metrohm buffer solutions other
reference and technical buffers are also included in the tables.
The following tables provide an overview of the stored pH(T) series.
Buffers marked with an * are not taken into account during automatic
buffer recognition if one of the complete sets of buffers is selected as
the buffer type. However, all the buffers listed can be selected to give a
new combination under
PARAMETER pH/calibration parameters/buffer type:
mixed
(see Section 6.2.2).
The pH values printed in bold are the values at the reference tempera-
ture of the particular buffer set.
The pH values marked with
1)
are interpolated or extrapolated values, all
the others correspond to the manufacturer's specifications.
Metrohm
NIST (according to DIN standard 19266, 2000)
Temp.
(°C)
Met4
Met7
Met9
NIST1
NIST4
NIST7
NIST9
NIST13
pH 4.00
pH 7.00
pH 9.00
pH 1
pH 4
pH 7
pH 9
pH 13
0
3.99
7.11
9.27
-
4.010
6.984
9.464
13.423
5
3.99
7.08
9.18
1.668
4.004
6.950
9.392
13.207
10
3.99
7.06
9.13
1.670
4.001
6.922
9.331
13.003
15
3.99
7.04
9.08
1.672
4.001
6.900
9.277
12.810
20
3.99
7.02
9.04
1.676
4.003
6.880
9.228
12.627
25
4.00
7.00
9.00
1.680
4.008
6.865
9.184
12.454
30
4.00
6.99
8.96
1.685
4.015
6.853
9.144
12.289
35
4.01
6.98
8.93
1.691
4.025
6.843
9.107
12.133
40
4.02
6.98
8.90
1.697
4.036
6.837
9.076
11.984
45
4.03
6.97
8.87
1.704
4.049
6.834
9.046
11.841
50
4.04
6.97
8.84
1.712
4.064
6.833
9.018
11.705
55
4.06
6.97
8.81
1.715
4.075
6.834
8.985
11.574
60
4.07
6.97
8.79
1.723
4.091
6.836
8.962
11.449
65
4.09
6.98
8.76
1.732
1)
4.108
1)
6.840
1)
8.941
1)
-
70
4.11
6.98
8.74
1.743
4.126
6.845
8.921
-
75
4.13
6.99
8.73
1.754
1)
4.145
1)
6.852
1)
8.902
1)
-
80
4.15
7.00
8.71
1.766
4.164
6.859
8.885
-
85
4.18
7.00
8.70
1.778
1)
4.185
1)
6.867
1)
8.867
1)
-
90
4.20
7.01
8.68
1.792
4.205
6.877
8.850
-
95
4.23
7.02
8.67
1.806
4.227
6.886
8.833
-