What are metals and nonmetals? Section 12-8

Metals and Nonmetals Look at p. 235, periodic table of the elements. Notice the dark zigzag line from top of group 13 to bottom of group 16. Everything to the right are nonmetals and everything to the left are metals.

Properties of metals and nonmetals All metals, except mercury (Hg), are solids at room temp. Hg is a liquid. Metals are shiny, they have luster. They can reflect light. Metals are malleable, able to be hammered into different shapes. Metals are ductile, they can be made into thin wires. Metals are good conductors of electricity (esp. copper Cu) and heat (like cooking pans). Nonmetals do not have luster, they look dull. Solid nonmetals are brittle, they break easily. Nonmetals cannot be pounded into different shapes or into thin wires. Nonmetals are poor conductors of heat and electricity. Nonmetals may exist as solids, liquids or gases at room temp.

What are the inert gases? Section 12-9

Inert Gases Located in group 18. They are all gases. They are also known as Noble gases. Inert means “inactive”. They will not combine with any other element. All inert gases occur in small amounts in the Earth’s atmosphere. Most common is argon (Ar).

Uses of inert gases Ne lights. When electricity passes through the gas, a bright red light is emitted. By mixing Ne with other gases like Ar and Kr produce different colors. He is used to fill balloons. Xe is used in photographic lamps. Rn , which is radioactive, is used to treat cancer.

H. W. p. 235 Check/apply 1-10 Wkst. 12-8 p. 239 check/apply 1-8 wkst