In such cases the symbol is the first letter of the element’s name followed by one other letter in the name. Since there are not enough single letters to go around and several elements may start with the same letter, other letters must sometimes be added. Simple symbols for chemical elements: Latin names Simple symbols for chemical elements: common names The symbol for potassium is K, after kalium, the Latin name for that element. For example, the symbol for hydrogen is H for carbon, C for uranium, U. Wherever possible, the symbol is the first letter of the common name or the Latin name of the element. Symbols for elements may have one letter or two. In 1789 the French chemist Antoine-Laurent Lavoisier made the first attempt to list elements based on the modern definition.Įach element has a symbol that is used by chemists around the world as a kind of shorthand. He pointed out that earth, air, fire, and water cannot be extracted from other substances or combined to form them. One of the first people to define elements in the modern sense was the British chemist Robert Boyle, in 1661. Later Greek thinkers, including Empedocles and Aristotle, believed that there were four elements: earth, air, fire, and water. The philosopher Thales believed that the essential substance was water, while Heraclitus thought that it was fire. Early Greek philosophers did believe that there are fundamental substances from which all matter is made, but their understanding of those substances varied from the modern definition of an element. But they were not then recognized as elements. Some substances now recognized as elements-copper, iron, silver, tin, gold, mercury, and lead-were known in ancient times because they are present in the Earth in relatively pure form. (68 ☏) to an equal volume of pure water at 4 ☌ (39.2 ☏). Specific gravity of liquids and solids is given as the ratio of the mass of the element at 20 ☌ **Density of gases is given as the weight in grams of 1 milliliter of the gas at 0 ☌ (32 ☏) and pressure of 760 millimeters In parentheses is the mass number of the most stable isotope of that element. *Atomic weights are based on carbon-12, the standard chosen in 1961 by the Commission on Atomic Weights. Saving Earth Britannica Presents Earth’s To-Do List for the 21st Century.Names and symbols of the elements element.Britannica Beyond We’ve created a new place where questions are at the center of learning.100 Women Britannica celebrates the centennial of the Nineteenth Amendment, highlighting suffragists and history-making politicians.
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