Volume 1
A dictionary of applied chemistry / by Sir Edward Thorpe, assisted by eminent contributors.
- Thomas Edward Thorpe
- Date:
- 1912-1913
Licence: Public Domain Mark
Credit: A dictionary of applied chemistry / by Sir Edward Thorpe, assisted by eminent contributors. Source: Wellcome Collection.
21/776 page 9
![(Perkin). The liquid is uninflammable, but the vapour burns with a blue flame producing water and carbonic acid. When passed through a red- hot tube only a small portion is decomposed, producing carbon, acetone, benzene, &c. The strong acid blackens when heated with concen¬ trated sulphuric acid, evolving sulphurous and carbonic anhydrides. Nitric and chromic acids have no action ; for this reason acetic acid is frequently used as a solvent for organic substances such as hydro¬ carbons, which are to be subjected to the action of chromic acid. Chlorine under the influence of sunlight replaces a portion of the hydrogen, and produces 'mono-, di- and trichloracetic acids. Similarly, bromine produces dibromacetic acid. On the addition of water to the glacial acid heat 9 is evolved and the density increases until 20 p.c. of water is present; from this strength to 23 p.c. of water the density remains stationary. Further dilution lowers the density, so that either dilution or concentration from this point will produce an acid of diminished density. An acid containing only 43 p.c. of acid has the same density as the glacial acid. This, together with the slight difference between the density of acetic acid and water, renders it impossible to determine, with any precision, the percentage of acid by means of the hydrometer. No definite hydrates of acetic acid are known (De Coppet, Ann. Chim. Phys. [7] 16, 275 ; Colles, Chem. Soc. Trans. 1906, 1247). The following table shows the density of aqueous acetic acid at 15° and 20° : Density of Aqueous Acetic Acid (Oudemans). p.c. Density p.c. Density p.c. Density 15° 20° 15° 20° 15° 20° 0 0-9992 0-9983 34 1-0459 1-0426 68 1-0725 1-0679 •1 1-0007 0-9997 35 1-0470 1-0437 69 1-0729 1-0683 2 1 0022 1-0012 36 1-0481 1-0448 70 1-0733 1-0686 3 1-0037 1-0026 37 1-0492 1-0458 71 1-0737 1-0689 4 1 0052 1-0041 38 1-0502 1-0468 72 1-0740 1-0691 5 1-0067 1-0055 39 1-0513 1-0478 73 1-0742 1-0693 6 1-0083 1-0069 40 1-0523 1-0488 74 1-0744 1-0695 7 1-0098 1-0084 41 1-0533 1-0498 75 1-0746 1-0697 8 1-0113 1-0098 42 1-0543 1-0507 76 1-0747 1-0699 9 1-0127 1-0112 43 1-0552 1-0516 77 1-0748 1-0700 10 1-0142 1-0126 44 1-0562 1-0525 78 1-0748 1-0700 11 1-0157 1-0140 45 1-0571 1-0534 79 1-0748 1-0700 12 1-0171 1-0154 46 1-0580 1-0543 80 1-0748 1-0699 13 1-0185 1-0168 47 1-0589 1-0551 81 1-0747 1-0698 14 1*0200 1-0181 48 1-0598 1-0559 82 1-0746 1-0696 15 1-0214 10195 49 1-0607 1-0567 83 1-0744 1-0694 16 1-0228 1-0208 50 1-0615 1-0575 84 1-0742 1-0691 17 1-0242 1 0222 51 1-0623 1-0583 85 1-0739 1-0688 ' 18 1-0256 1 0235 52 1-0631 1-0590 86 1-0736 1-0684 19 1-0270 1-0248 53 1-0638 1-0597 87 1-0731 1-0679 20 1-0284 1-0261 54 1-0646 1-0604 88 1-0726 1*0674 21 1-0298 1-0274 55 1-0653 1-0611 89 1-0720 1-0668 22 1-0311 1-0287 56 1-0660 1-0618 90 1-0713 1-0660 23 1-0324 1-0299 57 1-0666 1-0624 91 1-0705 1-0652 24 1 0337 1-0312 58 1-0673 1-0630 92 1-0696 1-0643 25 1-0350 1-0324 59 1-0679 1-0636 93 1-0686 1-0632 26 1-0363 1-0336 60 1-0685 1-0642 94 1-0674 1-0620 27 1-0375 1-0348 61 1-0691 1-0648 95 1-0660 1-0606 28 1-0388 1-0360 62 1-0697 1-0653 96 1-0644 1-0589 29 1-0400 1-0372 63 1-0702 1-0658 97 1-0625 1-0570 30 1-0412 1-0383 64 1-0707 1-0663 98 1-0604 1-0549 31 1-0424 1-0394 65 1-0712 1-0667 99 1-0580 1 0525 32 1-0436 1-0405 66 1-0717 1-0671 100 1-0553 1-0497 33 1-0447 1-0416 67 1-0721 1-0675 The addition of a small quantity of water lowers the melting-point of the glacial acid considerably, as shown by the annexed table (p. 10) Dahms (Ann. Chim. Phvs. [7] 18, 141). Acetic acid is monobasic, but forms both acid and basic, as well as normal salts. It dissolves certain metallic oxides, as those of lead and copper, forming basic acetates. It has a pungent sour taste, and when strong blisters the skin. The glacial acid has no action on litmus, but on addition of water becomes powerfully acid. It is not affected by the electric current, probably because a bad conductor, but when a little sulphuric acid is added the current decomposes it, producing, ac¬ cording to Renard (Ann. Chim. Phys. [5] 16, 289), carbon dioxide, carbon monoxide and oxygen. Alkaline acetates when electrolysed are decom¬ posed into hydrogen and alkaline hydrate which](https://iiif.wellcomecollection.org/image/b31355080_0001_0021.jp2/full/800%2C/0/default.jpg)
