Chemical-elements sentence example
For the characters of metals as chemical elements see the special articles on the different metals.
Though an alchemist, Boyle, in his Sceptical Chemist (1661), cast doubts on the " experiments whereby vulgar Spagyrists are wont to endeavour to evince their salt, sulphur and mercury to be the true principles of things," and advanced towards the conception of chemical elements as those constituents of matter which cannot be further decomposed.
He held the doctrine that the chemical elements are compounds of equal and similar atoms, and might therefore possibly be all derived from one generic atom.
He not only agrees with Laplace and Lyell about the evolution of the solar system, but also supposes that the affinities, pointed out by Lothar Meyer and Mendeleeff, between groups of chemical elements prove an evolution of these elements from a primitive matter (prothyl) consisting of homogeneous atoms. These, however, are not ultimate enough for him; he thinks that everything, ponderable and imponderable or ether, is evolved from a primitive substance, which condenses first into centres of condensation (pyknatoms), and then into masses, which when they exceed the mean consistency become ponderables, and when they fall below it become imponderables.
As to colour, he follows Goethe, and uses strong language against Newton's theory, for the barbarism of the conception that light is a compound, the incorrectness of his observations, &c. In chemistry, again, he objects to the way in which all the chemical elements are treated as on the same level.Advertisement
He was one of the first, if not quite the first, to propound the conception of periodicity among the chemical elements.
Both ideas, or both modes of expressing what is fundamentally the same idea, have this in common, that life is not a sum of the qualities of the chemical elements contained in protoplasm, but a function first of the peculiar architecture of the mixture, and then of the high complexity of the compounds contained in the mixture.
The chemical elements involved are abundant; the physical conditions of temperature pressure and so forth at which living matter is most active, and within the limits of which it is confined, are familiar and almost constant in the world around us.
The latter is considered below; " The Black .,, it is i nd i cat i ve of the chemical elements from which the lines can proceed, and its state at the time of emission; the former is indicative only of the rate of loss of energy from the sun by radiation, and is inwoven with a remarkable group of physical theory and experiment, known as the theory of the black body, or as black radiation.
Iron, calcium and hydrogen may be especially mentioned as three familiar chemical elements which enter largely into the constitution of all the matter of the heavens.Advertisement
Such substances are derived from (z) the chemical elements and their compounds; (2) plants; and (3) animals.
The key assumption of Dalton's chemical atomism is that chemical elements are composed of ' ultimate particles ' or atoms.
Working together, Marie and her husband Pierre, discovered the chemical elements radium and polonium.
Minerals-Inorganic chemical elements that are found in plants and animals and are essential for life.
Heavy metals are chemical elements that have a specific gravity (a measure of density) at least five times that of water.Advertisement
Heavy metal-One of 23 chemical elements that has a specific gravity (a measure of density) at least five times that of water.