The cyanide and bisulphite solution is then added with warming till the blue colour is destroyed.
The bisulphite processes depended in the earlier stages upon the efficiency of lead-lined digesters.
This is generally known as a solution of bisulphite of lime.
Sulphurous acid may either be applied in the gaseous form or in solution as bisulphite of soda.
bisulphite of soda has also often been used as the reducing agent.
If the bisulphite causes no bleaching, boil a piece of the paper with very dilute hydrochloric acid.
Among the better known agents which have such an effect upon latex, formalin and sodium sulphite (not bisulphite) are the chief.
Wool may also be bleached by steeping in a fairly strong solution of bisulphite of soda and then washing well in water.
Sometimes a mixture of bisulphite and powdered zinc replaces it, but this is objectionable for pure food gelatines.
bisulfite bi·sul·fite (bī-sŭl'fīt')
The univalent inorganic acid group HSO3.
A salt of sulfurous acid containing this group.