Calculations of volumetric analysis ordinarily consist of transforming the quantity of tit...

Calculations of volumetric analysis ordinarily consist of transforming the quantity of titrant used (in chemical units) to a chemically equivalent quantity of analyte (also in chemical units) through use of a stoichiometric factor. Use chemical formulas (NO CALCULATIONS REQUIRED) to express this ratio for calculation of the percentage of

*(a) hydrazine in rocket fuel by titration with standard iodine. Reaction:

H2NNH2 + 2I2 → N2(g) + 4I- + 4H+

(b) hydrogen peroxide in a cosmetic preparation by titration with standard permanganate. Reaction:

*(c) boron in a sample of borax, Na2B4O7 • 10H2O, by titration with standard acid. Reaction:

B4O72- + 2H+ + 5H2O → 4H3BO3

(d) sulfur in an agricultural spray that was converted to thiocyanate with an unmeasured excess of cyanide. Reaction:

S(s) + CN- → SCN-

After removal of the excess cyanide, the thiocyanate was titrated with a standard potassium iodate solution in strong HCl. Reaction: