1. Unit 4 Review
2014

2. 1. What are the horizontal rows called on the periodic table?
Periods

3. 2. Draw a Bohr Model for:
A. Carbon
B. Sodium
C. Lithium

4. 3. Explain what happens when electrons emit light
When electrons absorb energy they jump to a higher orbital (excited state). They then return to their starting point (ground state) and emit light!

5. 4. Describe an electron cloud.
The space around the nucleus of an atom where the electrons are orbiting extremely fast

6. 5. The regions (circles) of space in which the electrons are moving around the nucleus of an atom are called:
Energy levels (or orbitals, electron shells, or rings)

7. 6. Electrons in the outermost energy level are called:
Valence electrons

8. 7. What are the vertical columns called on the periodic table?
Groups or families

9. 8. What does a group tell you about an atom?
The number of valence electrons

10. 9. Draw a Lewis structure for:
A. Chlorine
B. Oxygen

11. 10. What is the family name for group 1?
Alkali metals

12. 11. What family name is Fluorine found in?
The Halogens (group 17)

13. 12. What is the family name for group 18?
The noble gases
Why are they called the noble gases?
-because their outmost energy level is full and have 8 valence electrons or a full outer shell causes an atom to be stable and therefore, unreactive

14. 14. Who first organized the elements into groups of 3 and what where those groups of 3 called?
Dobereiner; triads

15. 15. Who organized the periodic table into rows and columns and put them in by increasing atomic mass?
Mendeleev

16. 16. Henry Mosely understood that the elements are not organized by increasing atomic mass, but by the increasing_________ ___________
Atomic number

17. 17. How many valence electrons does Phosphorous have?5
Iodine? 7

18. 18. Explain why oxygen and sulfur have similar reactivities?
They both are in the same family/group and therefore have the same number of valence electrons

19. 19. List some properties of a metal
Shiny/luster
High densities
Good conductors
Mostly gray in color
Malleable
ductile

20. 20. List some properties of Non- metals
Brittle
More colorful
Mostly gases
Poor conductors of electricity

21. 21. Properties of Metalloids
Solids.
Can be shiny or dull.
Ductile.
Malleable.
Conduct heat and electricity better than nonmetals but not as well as metals.