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 modern periodic table is based closely on the ideas he used ... For example, lithium (Li), sodium (Na) and potassium (K) all have the same kind of reaction with water. The group of elements ...

The modern periodic table is based closely on the ideas he used ... For example, lithium (Li), sodium (Na) and potassium (K) all have the same kind of reaction with water. The group of elements ...