Paragraph 8 EXPRESSION OF RESULT

Express the result of the analysis as a percentage of chloride contained in the sample as it has been received for analysis.

Calculation: calculate the percentage of chloride (Cl) with the formula:

$$\mathrm{\%}\mathrm{Cl}=0.003546\times \genfrac{}{}{0.1ex}{}{\left(\mathrm{V}\mathrm{z}-\mathrm{V}\mathrm{cz}\right)-\left(\mathrm{V}\mathrm{a}-\mathrm{V}\mathrm{ca}\right)\times 100}{\mathrm{M}}$$

where:

• V_z = number of millilitres of silver nitrate added

• V_cz = number of millilitres of silver nitrate used in the blank test

• V_a = number of millilitres of ammonium thiocyanate used for the titration of the sample

• V_ca = number of millilitres of ammonium thiocyanate used for the titration of the blank

• M = mass in grams of the sample in aliquot volume taken for titration