These are washed with ammonium chloride until the filtrate is colourless, ignited, fused with caustic potash and nitre, the melt dissolved in water and nitric acid added to the solution until the colour of potassium ruthenate disappears.
A precipitate of ruthenium oxide gradually separates; this is collected and ignited in a graphite crucible and finally fused in the oxyhydrogen furnace (H.
This uranate when ignited in a platinum crucible leaves a green oxide of the composition U308, i.e.
When ignited in a current of hydrogen it yields tiianium trifluoride, TiF 3, as a violet powder.
The precipitate obtained is filtered, well washed with hot water, dried and then ignited until the weight is constant.