Periodic Table Notes

Who Made It? Russian chemist Demitri Mendeleev was the man responsible for the first P.T. His periodic table was arranged in order of increasing atomic mass. He predicted undiscovered elements and their properties.

Who Perfected the Table? British chemist Henry Mosely perfected the table. He discovered the atomic number of elements and arranged the elements in order of increasing atomic number. The periodic law states that the physical and chemical properties of elements are periodic functions of their atomic number.

Design of the Periodic Table Columns of elements are called groups or families. Groups or families are elements that have similar, but not identical properties They run up and down on the table. Rows of elements are called periods. Elements in a period do not have properties that are not alike. Periods run left to right across the periodic table.

The Element Key Information about each element is given in each square of the periodic table. Atomic number Chemical symbol Name Atomic mass

Metals Most elements are metals. Physical properties of metals include: Luster, good conductors, ductile, malleable Chemical properties of metals include: Tend to lose electrons when combined and they will corrode.

Nonmetals Physical properties of nonmetals include: No luster, brittle, poor conductors Chemical properties of nonmetals include: Tend to gain electrons when combined,

Metalloids Metalloids have properties of both metals and nonmetals.