Organic Chemistry for the Laboratory (Paperback)

This historic book may have numerous typos, missing text, images, or index. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. 1897. Not illustrated. Excerpt: ... Reagents. In very many operations in organic chemistry, success depends on the use of reagents in definite quantities, and in almost all cases it is an advantage to know quite accurately how much of each substance is present. Students should acquire the habit, therefore, of using solutions of known strength, and of weighing or measuring the substances and solutions used. This is greatly facilitated by knowing the strength, approximately, of the common laboratory reagents, and by having always at hand certain strong solutions of substances often used. Facility in making quick, approximate calculations of quantities reacting, is necessary, and this is often aided by using the number of grams, or deci-, or centigrams of a body corresponding to its molecular weight. Among the solutions which are especially useful in organic work, and which are of strengths different from the ordinary laboratory reagents, may be mentioned the following: Hydrochloric Acid.--Sp. gr. 1.n. One cc. contains 0.25 gram HC1, or 4 cc. = i gram HC1. One gram contains 0.224 gram HC1. This acid is approximated closely by diluting concentrated pure hydrochloric acid with an equal volume of water. Sulphuric Acid.--Sp.gr. 1.55. One cc. contains i gram H, SO4, or i gram contains 0.645 gram H, SO4. This acid is closely approximated by diluting pure concentrated sulphuric acid with an equal volume of water Sodium Hydroxide.--Sp. gr.'i.2g. Onecc. contains 0.335 gram NaOH, or 3 cc. = i gram. One gram contains 0.26 gram NaOH. The solution is approximated closely by dissolving 335 grams of pure sodium hydroxide in 700 cc. of water, and diluting the solution to one liter, when cold. The solution does not attack glass as readily as weaker solutions. Sodium Nitrite.--5 cc. -- i gram. Approximated by d...