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Chemical element, also called element, any substance that cannot be decomposed into simpler substances by ordinary chemical processes.
Elements are the fundamental materials of which all matter is composed.
Additional elemental qualities were introduced to accommodate newly discovered chemical transformations.
Thus, sulfur came to represent the quality of combustibility, mercury that of volatility or fluidity, and salt that of fixity in fire (or incombustibility).
The article also discusses the periodic law and the tabular arrangement of the elements based on it.
For detailed information about the compounds of the elements, At present there are 118 known chemical elements.
Elements can combine with one another to form a wide variety of more complex substances called compounds.
Thus, Greek thought encompassed the idea that all matter could be understood in terms of elemental qualities; in this sense, the elements themselves were thought of as nonmaterial.About 20 percent of them do not exist in nature (or are present only in trace amounts) and are known only because they have been synthetically prepared in the laboratory.Of the known elements, 11 (hydrogen, nitrogen, oxygen, fluorine, chlorine, and the six noble gases) are gases under ordinary conditions, two (bromine and mercury) are liquids (two more, cesium and gallium, melt at about or just above room temperature), and the rest are solids.Water clearly is not an element because it consists of, and actually can be decomposed chemically into, the two substances hydrogen and oxygen; these two substances, however, are elements because they cannot be decomposed into simpler substances by any known chemical process.Most samples of naturally occurring matter are physical mixtures of compounds.