1. Grouping the Elements

2. Key Words
Group/family
Properties
Outer energy levels
Reactivity

3. Main Ideas
Elements within each group/family, or column, on the periodic table have similar properties
This is because their atoms have the same number of electrons in their outer energy level
Hydrogen is set off by itself in the periodic table because its properties do not match the properties of any one group
By knowing which group an element is in, you can predict some of the element's properties

4. Group 1: Alkali Metals Group contains: metals
Electrons in outer level: 1
Reactivity: very reactive
Other shared properties: soft; silver-colored; shiny; low density

5. Group 2: Alkaline-earth Metals
Group contains: metals
Electrons in outer level: 2
Reactivity: very reactive, but less reactive than alkali metals
Other shared properties: silver-colored; more dense than alkali metals

6. Group 3-12 Transition Metals
Group contains: metals
Electrons in outer level: 1 or 2
Reactivity: less reactive than alkaline-earth metals
Other shared properties: shiny; good conductors of thermal energy and electric current; higher densities and melting points (except for mercury) than elements in Groups 1 or 2

8. Lanthanides and Actinides
Shiny, reactive metals
Some are used to make different types of steel
Actinides
Radioactive
Unstable
Can change into atoms of a different element
Elements after plutonium do not occur in nature but are produced in laboratories

9. Group13: Boron Group Group contains: one metalloid and four metals
Electrons in outer level: 3
Reactivity: reactive
Other shared properties: solid at room temperature

10. Group 14: Carbon Group
Group contains: one nonmetal, two metalloids, and two metals
Electrons in outer level: 4
Reactivity: varies among the elements
Other shared properties: solid at room temperature

11. Group 15: Nitrogen Group
Group contains: two nonmetals, two metalloids, and one metal
Electrons in outer level: 5
Reactivity: varies among the elements
Other shared properties: all but nitrogen are solid at room temperature

12. Group 16: Oxygen Group
Group contains: three nonmetals, one metalloid, and one metal
Electrons in outer level: 6
Reactivity: reactive
Other shared properties: all but oxygen are solid at room temperature

13. Group 17: Halogens Group contains: nonmetals
Electrons in outer level: 7
Reactivity: very reactive
Other shared properties: poor conductors of electric current; react violently with alkali metals to form salts; never found in uncombined in nature

14. Group 18: Noble Gases Also known as INERT gases
Group contains: nonmetals
Electrons in outer level: 8 (2 for helium)
Reactivity: unreactive (NOT reactive)
Other shared properties: colorless, odorless gases at room temperature

15. Hydrogen stands apart Electrons in outer level: 1 Reactivity: reactive
Other shared properties: colorless, odorless gas at room temperature; low density; reacts explosively with oxygen