All tests must use reagent-grade chemicals

. All reagents must conform to the set specifications, where such specifications are available. Use other grades only if the reagents are of high purity to allow its use without compromising the accuracy of the experiment.

1. Water—Reagent water used for the preparation of chemical solutions must meet Specification D 1193, Type IV.
2. Dissolve 20g of Sb2O3 or 32 g of SbCl3 in 1000 mL of Hydrochloric Acid to form Antimony Trichloride Solution
3. Concentrated hydrochloric acid (HCl)
4. Add 5 mL of antimony trichloride solution to 100 mL of Hydrochloric acid to form the HCl—Antimony Trichloride Solution
5. Add 500 ml of reagent water to 500 ml of hydrochloric acid, mix and allow it to cool to room temperature.

Precaution

Stibine is a poisonous gas, which may be evolved in small amounts along with hydrogen, has during the HCl – antimony trichloride method. HCl fumes are also present during the stripping process. The test must therefore be done in adequately ventilated environment. It is standard procedure to use a fume hood when experimenting with many samples or when the test is done frequently over a long time (Thompson, Ellison & Wood, 2006).

Sampling

Zinc-Coated Steel Sheets—Selection of samples for determination of weight or mass must be according to Specifications A 653/A 653M, A 792/A 792M, or A 875/ A 875M as per the type of coating (ASTM Standard A90, 2007).