The ratio of each element is usually expressed by chemical formula. For example, water (H2O) is a compound consisting of two hydrogen atoms bonded to an oxygen atom. Skip to main content.

Chemical symbols are usually one or two letters long.Every chemical symbol starts with a capital letter, with the second letter written in lower case.For example, Mg is the correct symbol for ...

If you would like to learn more about the IAEA’s work, sign up for our weekly updates containing our most important news, multimedia and more. Uranium is a naturally occurring radioactive element, ...

Each entry contains the atomic number, chemical symbol, and atomic mass to two decimal places on elements where data is available. Undefined cells contain a space. Row 9 is blank, and the content in ...

In this periodic table of elements quiz, you have 10 minutes to name as many elements as you can, given only their symbol, atomic weight and the broad group they live in.

Uranium (chemical symbol U) is a naturally occurring radioactive element. In its pure form it is a silver-coloured heavy metal, similar to lead, cadmium and tungsten. Like tungsten it is very dense, ...