Paragraph 8 EXPRESSION OF RESULTS

The percentage of trace element (E) in the fertiliser is given by:

$$\mathrm{E}\left(\mathrm{\%}\right)=\mathrm{[}\left(\mathrm{x}\mathrm{s}-\mathrm{x}\mathrm{b}\right)\times \mathrm{V}\times \mathrm{D]}/\left(\mathrm{M}\times 104\right)$$

If Method 26c has been used:

$$\mathrm{E}\left(\mathrm{\%}\right)=\mathrm{[}\left(\mathrm{x}\mathrm{s}-\mathrm{x}\mathrm{b}\right)\times \mathrm{V}\times \mathrm{2D]}/\left(\mathrm{M}\times 104\right)$$

where:

• E is the amount of the trace element determined, expressed as a percentage of the fertiliser;

• x_s is the concentration of the Fe or Zn in the test solution (6.2), in μg/ml;

• x_b is the concentration of the Fe or Zn in the blank solution (7.1), in μg/ml;

• V is the volume of the extract obtained by Method 26a or 26b, in ml;

• D is the factor corresponding to the dilution carried out in (6.2);

• M is the mass of the test sample taken in accordance with Method 26a or 26b in grams.

Calculation of dilution factor D:

If (a₁), (a₂), (a₃), . . ., (a_i) and (a) are the aliquot portions and (v₁), (v₂), (v₃), . . . , (v_i) and (100) are the volumes in ml corresponding to their respective dilutions, the dilution factor D will be equal to:

$$\mathrm{D}=(\mathrm{v}1/\mathrm{a}1)\times (\mathrm{v}2/\mathrm{a}2)\times (\mathrm{v}3/\mathrm{a}3)\text{x . . . x(v}\mathrm{i}/\mathrm{a}\mathrm{i})\times (100/\mathrm{a})\mathrm{.}$$