Symbols of Elements
2 Minutes
Symbols of elements for students: learn how chemical symbols evolved from Greek signs and Dalton to Berzelius. A science lesson in English.
- Greek and alchemist pictorial symbols for elements and water
- Dalton's circle symbols and Berzelius's letter-based system
- Rules using first, second, or Latin letters to name elements
What this lesson teaches
Chemical symbols are standard signs and letters used to represent elements and compounds. Over time, these representations changed from ancient hand-drawn figures into a practical letter-based system designed to make writing and identifying elements simple and clear.
Greek signs and alchemist pictorial symbols
- Long ago, people living in Greek cities created distinct symbols to represent the four basic parts of nature: land, water, air, and fire, with each symbol differing in its own way.
- In the eighth century, people known as alchemists attempted to transform cheap and easily available materials into valuable gold.
- Because alchemists worked with many different substances in their search for gold, they devised special alchemist symbols to represent each of those elements.
- Several of these alchemist signs, particularly those used for nickel, arsenic, antimony, and water, resembled detailed drawings and were known as pictorial symbols.
Dalton circular symbols
Because complex pictorial drawings were very difficult to sketch quickly, an English scientist named Dalton invented a new system of symbols. His method relied on simple geometric shapes rather than intricate pictures. For instance, he used an open circle to represent oxygen and a circle with a single dot placed at its center to represent hydrogen. When he wanted to represent a compound substance like water, he combined the circular oxygen symbol and the hydrogen symbol together.
Berzelius letter-based system
Even Dalton circular shapes proved difficult to draw repeatedly, prompting a chemist named Berzelius to replace pictures entirely by writing the first letters of element names separately. Under this system, O stood for oxygen, H stood for hydrogen, and B stood for boron. However, a problem arose because several elements, including barium, bromine, argon, and aluminium, shared the very same initial letter. To tell these elements apart, scientists began combining the first letter and the second letter of each element name into a two-letter symbol.
Resolving naming conflicts
- Another difficulty appeared when different elements shared their first two letters, as seen with chlorine and chromium.
- To resolve this overlap, symbols were formed by combining the first letter and the third letter of the name, giving Cl for chlorine and Cr for chromium.
- Some elements do not follow the letters of their modern common names, such as sodium and potassium, which take their symbols from Latin letters instead.
- Element names and their symbols can also be derived from other sources, including colors, countries, scientists, mythological characters, and planets.