Dissolve the residue in a small quantity of hot water and moisten a piece of turmeric paper with the solution.
If turmeric paper be dipped into a solution of a borate, and then be dried at 100° C., it is turned to a peculiar red color.
It should be colourless, without action on either litmus or turmeric paper, and have the boiling-point, sp.
The machine was then worked, the positive electricity passing into the turmeric paper at the point p, and out at the extremity n.
When applied to turmeric paper, it first reddened and then bleached it.
The pole c, when touched by turmeric paper, gave no traces of alkali, nor could anything but pure water be found upon it.
turmeric paper may be prepared by dipping pieces of smooth, thin filter paper in a solution of powdered turmeric in alcohol.
Then test with the turmeric paper with the same results as in the above method.
If boric acid either free or combined is present, the turmeric paper will be turned to a cherry-red color.
Soak a piece of turmeric paper in the extract, and if boric acid is present the paper will be colored rose-red when it is dry.