Study Set Content:
Assay of Zinc Oxide
Other Names:
Zinc white, Calamine, Philosopher’s wool, Chinese white, flowers of zinc
Assay of Zinc Oxide
Chemical Formula
ZnO
Assay of Zinc Oxide
MW
81.38g/mol
Assay of Zinc Oxide
Appearance:
White, odorless solid
Assay of Zinc Oxide
Chemical Formula
ZnO + H2SO4 ZnSO4 + H2O
Assay of Zinc Oxide
ANALYTE
ZnO
Assay of Zinc Oxide
INDICATOR
Methyl Orange
Assay of Zinc Oxide
VISUAL END POINT
Yellow
Frequently used when a reaction proceeds slowly or when the substance to be assayed does not give a distinct, sharp end point with an indicator by direct titration.
Residual Titration/ Back Titration
How many drops indicator test solution for a titration unless otherwise directed
3
when a strong acid is titrated with a strong alkali, or a strong alkali with a strong acid
Methyl orange, methyl red or phenolphthalein may be used
when a weak acid is titrated with a strong alkali, use
phenolphthalein
When a weak alkali is titrated with a strong acid
Use methyl red as indicator
a weak alkali should never be titrated with
a weak acid and vice versa
. the appearance of a color is more easily observable than the disappearance. Therefore always titrate where possible to the
Appearance of a color
