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 ...

The table shows the melting points of five alkali metals. Use this information to describe how melting point changes in group 1.

The actual boiling point of radon is -61.7˚C. An estimate would lie midway between -100˚C and -50˚C based on the shape of the graph.