Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Nickel Sulfate Hexahydrate (Nickel(II) Sulfate Hexahydrate; Nickelous Sulfate Hexahydrate) Part 4, Monographs for Reagent Chemicals: General Descriptions, Specifications, and Tests eISBN: 9780841230460 Tom Tyner Chair, ACS Committee on Analytical Reagents James Francis Secretary, ACS Committee on Analytical Reagents
ABSTRACT This monograph for Nickel Sulfate Hexahydrate provides, in addition to common physical constants, a general description including typical appearance, applications, change in state (approximate), and aqueous solubility. The monograph also details the following specifications and corresponding tests for verifying that a substance meets ACS Reagent Grade specifications including: Assay, Insoluble Matter, Chloride, Nitrogen Compounds, Calcium, Cobalt, Copper, Iron, Magnesium, Manganese, Potassium, and Sodium.
NiSO4 • 6H2O
Formula Wt 262.85
CAS No. 10101-97-0
GENERAL DESCRIPTION Typical appearance . . . . . . . . . . . . . . . . . . . blue to green solid Applications . . . . . . . . . . . . . . . . . . . . . . . . source of nickel in standards Change in state (approximate) . . . . . . . . . . . . melting point, loses 5 H2O at 100 °C; greenish-yellow anhydrous salt forms at 280 °C Aqueous solubility . . . . . . . . . . . . . . . . . . . . soluble in 1.4 parts water
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98.0–102.0% NiSO4 · 6H2O Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.005% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 0.001% Nitrogen compounds (as N) . . . . . . . . . . . . . . 0.002% Calcium (Ca) . . . . . . . . . . . . . . . . . . . . . . . 0.005% Cobalt (Co) . . . . . . . . . . . . . . . . . . . . . . . . 0.002% Copper (Cu) . . . . . . . . . . . . . . . . . . . . . . . . 0.005% Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.001% Magnesium (Mg) . . . . . . . . . . . . . . . . . . . . . 0.005%
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4240 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
Manganese (Mn) . . . . . . . . . . . . . . . . . . . . . 0.002% Potassium (K) . . . . . . . . . . . . . . . . . . . . . . . 0.01% Sodium (Na) . . . . . . . . . . . . . . . . . . . . . . . . 0.05%
TESTS Assay (By complexometric titration of nickel). Weigh accurately about 1 g, transfer to a 400 mL beaker, and dissolve in 250 mL of water. Add 10 mL of pH 10 ammoniacal buffer solution and about 50 mg of murexide indicator mixture. Titrate immediately with 0.1 M EDTA volumetric solution to a purple color. One milliliter of 0.1 M EDTA corresponds to 0.02628 g of NiSO4 · 6H2O.
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 20 g dissolved in 150 mL of water.
Chloride Dissolve 1.0 g in 15 mL of water, filter if necessary through a small chloride-free filter, and add 1 mL of nitric acid and 1 mL of silver nitrate reagent solution. Any turbidity should not exceed that produced by 0.01 mg of chloride ion (Cl) in an equal volume of solution containing the quantities of reagents used in the test. The comparison is best made by the general method for chloride in colored solutions, [Part 2: Colorimetry and Turbidimetry; Chloride].
Nitrogen Compounds [Part 2: Colorimetry and Turbidimetry; Nitrogen Compounds: Test for Ammonia, Amines, and Nitrogen Compounds Reduced by Aluminum]. Use 1.0 g. For the standard, use 0.02 mg of nitrogen ion (N).
Calcium, Cobalt, Copper, Iron, Magnesium, Manganese, Potassium, and Sodium (By flame AAS, [Part 2: Trace and Ultratrace Elemental Analysis; Atomic Absorption Spectroscopy; Analysis; Procedure for Flame AAS]).
For the Determination of Calcium, Cobalt, Copper, Iron, Magnesium, Manganese, Potassium, and Sodium
S a m p l e S t o c k S o l u t i o n . Dissolve 20.0 g of sample in 75 mL of water and 2 mL of nitric acid. Transfer to a 100 mL volumetric flask, and dilute to the mark with water (1 mL = 0.20 g).
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4240 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
For the Determination of Calcium, Cobalt, Copper, Iron, Magnesium, Manganese, Potassium, and Sodium
Element
Wavelength (nm)
Sample Wt (g)
Standard Added (mg)
Flame Type*
Background Correction
Ca
422.7
2.0
0.05; 0.10
N/A
No
Co
240.7
2.0
0.02; 0.04
A/A
Yes
Cu
324.8
2.0
0.05; 0.10
A/A
Yes
Fe
248.3
4.0
0.04; 0.08
A/A
Yes
Mg
285.2
0.20
0.005; 0.01
A/A
Yes
Mn
279.5
2.0
0.02; 0.04
A/A
Yes
K
766.5
0.20
0.01; 0.02
A/A
No
Na
589.0
0.04
0.01; 0.02
A/A
No
*A/A is air/acetylene; N/A is nitrous oxide/acetylene.
© 2017 American Chemical Society
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DOI:10.1021/acsreagents.4240 ACS Reagent Chemicals, Part 4