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Table 2015.18B. ICP calibration standards from commercial custom blend stock standard
solutions
Standard
ID
Volume,
mL
Citrate,
mL
Stock
2500 P
,
mL
a
Stock
7500 K,
mL
b
P concn,
µg/mL
P
2
O
5
,
µg/mL
P
2
O
5
solution,
%
P
2
O
5
fertilizer, %
K concn,
µg/mL
K
2
O,
µg/mL
K
2
O
solution, %
K
2
O
fertilizer, %
Blank
1000
400
0
0
0
0
0
0
0
0
0
0
1
250
100
10 of Std 7
NA
12
27.5
0.00275
1.4
360
434
0.04336
21.7
2
250
100
20 of Std 7
NA
24
55
0.00550
2.7
300
361
0.03614
18.1
3
250
100
5
NA
50
115
0.01146
5.7
240
289
0.02891
14.5
4
250
100
10
NA
100
229
0.02291
11.5
180
217
0.02168
10.8
5
250
100
15
NA
150
344
0.03437
17.2
120
144
0.01441
7.2
6
250
100
22
c
NA
220
504
0.05041
25.2
63
76
0.00759
3.8
7
250
100
30
NA
300
687
0.06874
34.4
NA
NA
NA
NA
8
250
100
40
NA
400
917
0.09165
45.8
33.6
40
0.00405
2.0
9
250
100
50
NA
500
1146
0.11457
57.3
16.8
20
0.00202
1.0
10
250
100
NA
25
NA
NA
NA
NA
450
542
0.05421
27.1
11
250
100
NA
30
NA
NA
NA
NA
600
723
0.07227
36.1
12
250
100
NA
35
NA
NA
NA
NA
750
903
0.09034
45.2
13
250
100
NA
35
NA
NA
NA
NA
900
1084
0.10841
54.2
14
250
100
NA
35
NA
NA
NA
NA
1050
1265
0.12648
63.2
a
Stock 1 = 2500 μg/mL P as PO
4
custom stock standard [see Alternative A, B(
p
)] Also, 10 of Std 7
represents a serial dilution from another standard, meaning take 10 mL from standard 7.
b
Stock 2 = 7500 μg/mL K from KCl custom stock standard [see Alternative A, B(
q
)].
c
22 mL can be achieved by using a 15 mL and a 7 mL class A pipet or equivalent combination.
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