Name: _________________________
Per: _____
Date: __________________
Periodic Trends Study Guide
Vocabulary (Level 2)
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Atomic radius
Ionization energy
Electronegativity
Metal (know the location on Periodic Table, properties, and why the properties are useful)
Nonmetal (know the location on Periodic Table, properties, and why the properties are useful)
Metalloid (know the location on Periodic Table, properties, and why the properties are useful)
Reactivity
Valence Electron
Energy level
Trend
Practice Problems (Level 2 and 3)
1. What is atomic radius? Distance from nucleus to outermost energy level of an atom, measured
in nanometers.
2. Which way does atomic radius increase on the periodic table? Why? Atomic radius increases as
you move down a group, because the atoms at the bottom of the group have more energy
levels. The energy levels occupy more space, and get further from the nucleus, causing the
radius to be larger. Radius also increases as you move right to left (bigger radius on left) because
atoms on the left have less protons. This means that the nucleus has a weaker positive charge,
and does not attract/pull in the electrons as close to the nucleus.
3. Which of the following would have the smallest atomic radius?
Ca K Na
4. Which of the following would have the largest atomic radius?
F
Cl
S
5. What is ionization energy? Amount of energy required to steal an electron from an atom
6. Which way does ionization energy increase on the periodic table? Why? Increases in opposite
direction of atomic radius. (gets bigger up and to the right) Hard to steal from atoms with a
small radius, because the protons are pulling the electrons in very strongly.
7. Which of the following would have the smallest ionization energy?
Ge
8. Which of the following would have the largest ionization energy?
Li
As
Be
P
Mg
9. What is electronegativity? Ability to attract electrons when bonding with another element.
(How likely an atom is to steal an electron from another atom.)
Name: _________________________
Per: _____
Date: __________________
10. Which way does electronegativity increase on the periodic table? Why? Increases up and to the
right. Atoms on the right are close to having 8 VE, so are willing/likely to steal electrons to fill
their orbital. (high electronegativity.) Atoms at the bottom are bad/not likely to steal electrons,
because there are so many energy levels blocking the protons. (protons cannot attract other
electrons with their positive forces. Low electronegativity)
11. Which of the following would have the smallest electronegativity? Cs Rb Sr
12. Which of the following would have the largest electronegativity?
Te
I Br
13. Where are the metals located on the periodic table? left
14. Where are the nonmetals located on the periodic table? right
15. Where are the metalloids located on the periodic table? Staircase pattern between metals and
nonmetals
16. Why are metalloids useful for building computer chips and other electronic components?
Refer to reading.
-conductive enough to be turned on and off/ conduct electrical current. Not so conductive that
they will overheat other electrical components. Price. Malleability. Consult reading for details.
Other Possible Level 3 Topics
1. If someone describes properties of a new element they discovered, be able to place it on the
periodic table.
2. If someone describes qualities that they want for building something, be able to explain what
element might work.
3. Be able to identify unknown elements based on reactivity and physical properties (like we did
with the DVC fire lab)
4. Explain WHY each of the periodic trends is the way it is. (Why does it increase left to right, right
to left, up and down, etc.)