A manual of chemistry, inorganic and organic : inorganic and organic, with an introduction to the study of chemistry / by Arthur P. Luff.

  • Arthur P. Luff
Date:
1892
Catalogue details

Licence: Public Domain Mark

Credit: A manual of chemistry, inorganic and organic : inorganic and organic, with an introduction to the study of chemistry / by Arthur P. Luff. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    sulphur from it; on treating it with dilute sulphuric acid, a gas, called sulphuretted hydrogen, possessing an offensive odour, is evolved ; neither iron nor sul- phur possesses the property alone of evolving this gas when treated with dilute sulphuric acid. As may be readily coni])rehended, a mixture of iron filings and sulphur could be made with any proportions of the constituents, whereas the chemical compound sulphide of iron requires the constituents to be present in the fixed proportions of 56 pai-ts by weight of iron to 32 parts by weight of sulpliur. (The student will shortly learn that these are the atomic or combining weights of iron and sulphur.) If different proportions to these are used, then a mixture of sulphide of iron with excess of either iron or sulphur will be the residt, accordingly as excess of iron or sulphur has been used. CJIiaractcrs of clicmical attraction.—It is necessary that the student should pay great attention to the peculiar characters by which the force of chemical attraction may be recognised, for it is by means of this force that the compiiratively few ele- mentary bodies arrange themselves into the number- less compounds of which the animal, vegetable, and mineral kingdoms are compo.sed. Chemical attraction is an -extremely powerful force, which acts only on the smallest particles of matter, and between inappreciable distances. An example of the last mentioned fact is obtained by powdering and rubbing together in a mortar tartaric acid and carbonate of soda; no change whatever occurs, for it is impossible by such means to bring the two substances into sufficiently close contact to react on one another; but if water be now added to the mixture in the mortar, the two substances will dissolve, and in the dissolved state svill come sufficiently close to one another to react, chemical action being mani-