Monograph pubs.acs.org/doi/book/10.1021/acsreagents
Lead Acetate Trihydrate (Lead(II) Acetate Trihydrate) 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 Lead Acetate Trihydrate 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, Nitrate, Nitrite, Calcium, Copper, Iron, Potassium, and Sodium.
(CH3COO)2Pb • 3H2O
Formula Wt 379.30
CAS No. 6080-56-4
GENERAL DESCRIPTION Typical appearance . . . . . . . . Applications . . . . . . . . . . . . . Change in state (approximate) . Aqueous solubility . . . . . . . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
. . . .
white or colorless solid detection of sulfide, chromate, and molybdenum trioxide melting point, 75 °C; decomposes at 200 °C 84 g in 100 mL at 40 °C
SPECIFICATIONS Assay . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9.0–103.0% (CH3COO)2Pb · 3H2O Maximum Allowable Insoluble matter . . . . . . . . . . . . . . . . . . . . . 0.01% Chloride (Cl) . . . . . . . . . . . . . . . . . . . . . . . 5 ppm Nitrate and nitrite (as NO3) . . . . . . . . . . . . . . 0.005% Calcium (Ca) . . . . . . . . . . . . . . . . . . . . . . . 0.005% Copper (Cu) . . . . . . . . . . . . . . . . . . . . . . . . 0.002% Iron (Fe) . . . . . . . . . . . . . . . . . . . . . . . . . . 0.001% Potassium (K) . . . . . . . . . . . . . . . . . . . . . . . 0.005% Sodium (Na) . . . . . . . . . . . . . . . . . . . . . . . . 0.01%
© 2017 American Chemical Society
A
DOI:10.1021/acsreagents.4186 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
TESTS Assay (By complexometric titration of Pb). Weigh accurately about 1.5 g, transfer to a 400 mL beaker, and dissolve in 250 mL of water containing 0.15 mL of acetic acid. Add 15 mL of saturated hexamethylenetetramine reagent solution. Add a few milligrams of xylenol orange indicator mixture and titrate with 0.1 M EDTA volumetric solution to a yellow color. One milliliter of 0.1 M EDTA corresponds to 0.03793 g of (CH3COO)2Pb · 3H2O.
Insoluble Matter [Part 2: Gravimetric Methods; Insoluble Matter]. Use 10 g dissolved in 100 mL of dilute glacial acetic acid (1:99) free from carbon dioxide.
Chloride [Part 2: Colorimetry and Turbidimetry; Chloride]. Use 2.0 g.
Nitrate and Nitrite [Part 2: Colorimetry and Turbidimetry; Nitrate; Procedure for Nitrate, Method 1 (Brucine Sulfate)].
For the Determination of Nitrate and Nitrite
S a m p l e S o l u t i o n A . Dissolve 0.20 g in 1 mL of water. Add 20 mL of nitrate-free sulfuric acid (2:1), centrifuge, and decant the liquid portion into a 200 mm test tube. Dilute to 50 mL with brucine sulfate reagent solution. C o n t r o l S o l u t i o n B . Dissolve 0.20 g in 1 mL of nitrate ion (NO3) standard solution. Add 20 mL of nitrate-free sulfuric acid (2:1), centrifuge, and decant the liquid portion into a 200 mm test tube. Dilute to 50 mL with brucine sulfate reagent solution.
Continue with the procedure, starting with the preparation of blank solution C.
Calcium, Copper, Iron, 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, Copper, Iron, Potassium, and Sodium
S a m p l e S t o c k S o l u t i o n A . Dissolve 25.0 g in 75 mL of water and 5 mL of nitric acid. Transfer to a 100 mL volumetric flask, and dilute to the mark with water (1 mL = 0.25 g). S a m p l e S t o c k S o l u t i o n B . Transfer 4.0 mL of sample stock solution A to a 100 mL volumetric flask, and dilute to the mark with water (1 mL = 0.01 g).
© 2017 American Chemical Society
B
DOI:10.1021/acsreagents.4186 ACS Reagent Chemicals, Part 4
ACS Reagent Chemicals
Monograph
pubs.acs.org/doi/book/10.1021/acsreagents
For the Determination of Calcium, Copper, Iron, Potassium, and Sodium
Element
Wavelength (nm)
Sample Wt (g)
Standard Added (mg)
Flame Type*
Background Correction
Ca
422.7
1.0
0.025; 0.05
N/A
No
Cu
324.7
1.0
0.02; 0.04
A/A
Yes
Fe
248.3
5.0
0.05; 0.10
A/A
Yes
K
766.5
1.0
0.025; 0.05
A/A
No
Na
589.0
0.10
0.005; 0.01
A/A
No
*A/A is air/acetylene; N/A is nitrous oxide/acetylene.
© 2017 American Chemical Society
C
DOI:10.1021/acsreagents.4186 ACS Reagent Chemicals, Part 4
