Periods and families in the periodic table are described. Organization of the Periodic Table: Periods and families in the periodic table are described. Students learn to determine the number of energy ...

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 ...

This lesson utilizes an adaptation of the board game Periodic: A Game of the Elements to help students better understand both general periodic trends and the law of conservation of energy. This ...

At the middle of the 19th century, 63 chemical elements were known to science. Before Mendeleev’s discovery, attempts at arranging them in some logical way were made by Johann Doebereiner (1829), ...