1. Section 4: Nonmetals and Metalloids
Objectives:
locate nonmetals and metalloids in the periodic table
compare the physical and chemical properties of nonmetals with those of metals, and describe the properties of metalloids

2. What is a Nonmetal? The element on the right side
of the zigzag line are nonmetals.
(yellow boxes)
•An element that does not have most of the properties of metal.

3. Physical Properties of Nonmetals
•low melting point
-many are gases at room temperature

4. Few are solids at room temperature
Examples: Sulfur, carbon, and iodine
Only bromine is a liquid at room temperature.
Most physical properties of nonmetals are opposite of the metals;
-dull, not shiny
-solid nonmetals are brittle (not malleable and not ductile)
-poor conductors of heat and electricity.

5. Chemical Properties of Nonmetals
Except for Group 18 most form compounds
-able to gain or share electrons
(usually do not loose electrons)
-Group 18 has full valence shells
do not easily loose or share electrons

6. Compound of Nonmetals Nonmetals usually react with metals
Valence electrons move from the metal atoms to the nonmetals
Example: table salt (NaCl)
sodium has 1 valence electron and chlorine has 7
Nonmetals can form compounds with
other nonmetals
forms diatomic molecules
such as oxygen and hydrogen

7. Families of Nonmetals Carbon is most important in chemistry of
living things
·All living thing
made up of
carbon.
Carbon only nonmetal is this family
Silicon and germanium are metalloids
Tin and lead are metal
Contain 4 valence electron

8. Diamonds and soot are both forms of
carbon.
Diamonds are the hardest material
materials. It is used as a jewel
and for saws, drills, and files.
Soot is very soft. It is used as pigment
in paints and crayons

9. Nitrogen Group Contain 5 valence electrons
80% of atmosphere is nitrogen
Most living things get nitrogen from food eaten
Some bacteria use nitrogen from the air

10. Phosphorus is in nitrogen group
Not stable as element
Must combine with other elements to form compounds

11. Oxygen Group Elements in this group share or gain 2 Electrons
Group contains 3 nonmetals
Important gas for all living things
Oxygen is most abundant element is
Earth crust and 2nd most abundant element in earths atmosphere

12. Sulfur is nonmetal in oxygen family
Used in production of rubber bands, tires, and medicines

13. Halogen Family All elements have 7 electron
Usually gains or shares one electron
All elements are nonmetals
Very reactive
Dangerous to humans in pure form

14. Halogens Fluorine used in nonstick cookware
and fluoridation of water to
fight tooth decay
Chlorine is used as disinfectant
found in table salt
Bromine is used in compound of silver bromide that is used in photographic film.
Iodine is used as disinfectant

15. Noble Gases Valence shell is full with 8 electrons
Very stable and unreactive
All are found in earth’s atmosphere in
small amounts

17. Hydrogen Stands Apart 1 proton and 1 electron
however chemical properties
are so different it is not
grouped into a family
90% of atoms in universe are
hydrogen, but only 1% of
mass of crust, oceans, and
atmosphere is hydrogen
Rarely found on earth as pure
element

18. Metalloids Areas shaded in green are metalloids
Have some characteristics of
metals and some of nonmetals

19. Most useful property of metalloid
is ability to conduct
electricity
Silicon and germanium
are used to make
semiconductor
Semiconductors carry electricity
under some conditions and
during other conditions
cannot carry electricity
Used in computer chips, transistors,
and lasers.