Lesson 10
280
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ARCO
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SAT II Subject Tests
Classification Questions
This type of question uses the same set of answer choices for several items.
EXAMPLE:
Questions 1–4 refer to the following elements:
(A) Li
(B) Si
(C) K
(D) Pb
(E) O
1. Which element has the lowest first ionization energy?
2. Which element has the highest electronegativity?
3. Which element can form tetrahalides?
4. Which element has the largest atomic radius?
These four questions require knowledge about how certain properties of elements vary within the
periodic table. The first question deals with the property of ionization energy.
Group IA elements have the
lowest first ionization energies within a given period; also, ionization energy
decreases from top to bot-
tom within a given group. Using these two statements, one can determine that K (potassium) has the
lowest first ionization energy.
The second question requires one to know how the property of electronegativity
varies in the peri-
odic table. Electronegativity increases from left to right in the periodic table. O, oxygen, a member of
group VIA, has the highest electronegativity.
To answer
the third question, one must examine the valence characteristics of the elements listed. Si,
silicon, which is a group IVA element, has four valence electrons that it can share
with four halogen atoms
to form a tetrahalide.
Question four deals with the property of atomic radius; atomic radius decreases
from left to right in
the periodic table but increases from top to bottom. Pb, lead, since it is so near the bottom of the table, has
the largest atomic radius.
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