Preparation of potassium thiocyanate
10 g sulfur powder, 5 g of potassium carbonate (anhydrous) and 14 g of yellow blood salt (potassium ferrocyanide) mix. Anhydrous yellow blood salt obtained by careful dehydration by heating the metal burner crystals lose their water of crystallization (ventilate and disintegrate into powder). Pour mixture into a crucible and thoroughly in an oven protavíme, if we do not use the oven for at least 2 burners. Cooled melt vyloužíme ethanol, filtered and set aside to crystallize. The crystals of potassium rhodanide recrystallized from ethanol.