The three-part of the periodic table include the metalloids, metals, and nonmetals. The periodic table is a simple systematic way of classifying elements. Periodic tables are used in chemistry. Mendeleev (1869), a Russian scientist was the first to formulate the periodic law based on the relative masses of the element.
The metals are on the left-hand side of the table, except hydrogen. Although hydrogen acts as metal in its solid-state at ordinary temperature it is a gas. Properties of metals include high electrical and thermal conductivity, metallic luster, hard and high melting point.
The metalloids are in between the metals and nonmetals. There is a zig line toward the right side of the periodic table which acts as a border between the metals and nonmetals. Metalloids are also called semimetals.
Nonmetals are on the right side of the periodic table. Properties of the nonmetals include lack of metallic luster, poor conductors of heat, and high ionization energy, and are often liquid or gas at room temperature.