The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

There are some exceptions though. For example, mercury is a liquid at room temperature. The metals in Group 1, such as lithium, sodium and potassium, are all soft. Many non-metals have low melting ...

There are 118 elements in the periodic table, each with a unique symbol and atomic number. Symbol: A one or two-letter abbreviation used to represent the element. Atomic number: The number of ...

But how many of these elements do you know? Test your knowledge and compete with other Live Science readers to see who can ...