Page:The British pharmacopœia.djvu/529

Rh grams (40 grains) of hydrate of sodium, and will therefore neutralise one. molecular weight in grains of any monobasic acid, or half the molecular weight in grains of any dibasic acid, etc.

Grammes and cubic centimetres may be employed instead of grains and grain-measures, but for convenience $1⁄10$ th. of the numbers should be taken. 100 cubic centimetres contain $1⁄10$ th of a molecular weight in grammes (4 grammes) of hydrate of sodium, and will neutralise $1⁄10$ th of a molecular weight in grammes of a monobasic acid.

This solution is used for testing the following substances : —

INDICATORS OF THE TERMINATION OF REACTIONS IN VOLUMETRIC OPERATIONS.

Mucilage of Starch. It gives an intense blue colour with iodine. It may be used with the following substances :—


 * Acidum Arseniosum
 * Sulphurosum
 * Calx Chlorinata
 * Iodum
 * Liquor Arsenicalis
 * Arsenici Hydrochloricus
 * Calcis Chlorinatas
 * Sodii Chlorinatfe
 * Chlori
 * Sodii Hyposulphis