Book Description

Excerpt from Laboratory Manual of Biological Chemistry: With Supplement Equivalent and Normal Solutions. - Since the molecular weight of sodium hydroxid (NaOH) is 40 and that of hydrochloric acid (HCl) is 36.46, it follows that 40 g. of the former contain the same number of molecules as 36.46 g. of the latter. If 40 g. of sodium hydroxid and 36.46 g. of hydrochloric acid are each dissolved in pure water sufficient to make one liter of solution, each liter will contain the same number of dissolved molecules. It will take a little less than one liter of water to make a liter of solution because the dissolved substance takes up some space. A normal sodium hydroxid solution contains four per cent, of sodium hydroxid. By per cent, in the case of solutions is usually meant the amount of substance present in 100 c.c. of solution. Mixing equal volumes of two such solutions is, therefore, the same as bringing together practically the same number of the two kinds of molecules, and the result is the instantaneous and essentially complete transformation into sodium chlorid (and water). X NaOH + X HC1 = X NaQ + X H2O If either or both of the solutions should first be diluted with a considerable bulk of pure water, the result on mixing the two would be the same, for the extra amount of water present takes no part in the reaction (except to the extent of absorbing a part of the heat set free). The two solutions are equivalent. They also happen to be normal solutions. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.