| If cyanide is present in concentrations above the linear working range, the sample solution has to be diluted accordingly with ultrapure water. |
| Dissolve anhydrous sodium carbonate and sodium hydrogen carbonate in 2 L of ultrapure water under stirring. |
| Alternatively the ultrapure water used can already be degassed before the addition of the reagents. |
| With this system, samples of widely different concentrations such as ultrapure water and drinking water can be injected. |
| To prepare the anion standard, these stock solutions are then diluted to the desired concentrations with ultrapure water. |
| These buffers are selected to consist of only a few substances easily represented in chemical form as ultrapure solutions mixed in simple ratios. |
