Video - Atoms and the periodic table

The periodic table is a chart that organizes all the known elements according to their atomic number (number of protons in the nucleus). The elements are arranged in rows and columns, with each element occupying a specific place on the table. Each element has a unique symbol that is used to represent it. For example, hydrogen is represented by H, lithium by Li, and oxygen by O. The atomic number of an element is represented by a superscripted number to the left of the element's symbol. For example, the atomic number of hydrogen is 1, so it is represented as H1.

The elements are arranged in increasing order of atomic number. As you move from left to right across a row, the atomic numbers increase. As you move down a column, the atomic numbers increase.