It is sometimes advisable to regulate the quantity of dichromate.
The dichromate is first dissolved, and the acid added gradually.
First mix the ammonia with the water, then grind up and add the dichromate.
Distilled with dichromate of potassium and sulphuric acid it is converted into benzoic acid.
Into this type fall also the liquors formed by passing sulphur dioxide gas into dichromate solution.
Of the third type the most common is that in which the dichromate is reduced by sulphuric acid and sodium bisulphite.
Other organic substances are also often used, instead of glucose, to reduce the dichromate.
After this it is well washed to remove the unaltered gum and dichromate salt.
The amount of hypo necessary is almost directly proportional to the amount of dichromate used.
dichromate di·chro·mate (dī-krō'māt', dī'krō-)
A compound containing the divalent negative ion, Cr2O7, usually having a characteristic orange-red color. Also called bichromate.