Organizing the elements

Dobereiner

• Triads

• Octaves

• Periodic Table

He arranged the elements in order of increasing atomic mass.

• Dobereiner

• Mendeleev’s

• Bohr

elements are arranged in order of increasing atomic number.

• modern Periodic Table

• Dobereiner Triads

• Mendeleev’s Periodic Table

The modern Periodic Table is made up of metals, nonmetals and metalloids.

• True

• False

Good conductors of heat and electricity.

• Metals

• Nonmetals

high luster

• Metals

• Nonmetals

All metals are solids at room temperature except..........

• sodium

• gallium

• mercury

can be drawn into wires

• Malleable

• Ductile

can be hammered into thin sheets without breaking.

• Malleable

• Ductile

Brittle substance

• metal

• nonmetal