The document discusses trends in the periodic table by providing multiple choice questions about ionic radii, quantum numbers, and atomic properties. It asks about the number of quantum numbers needed to define orbitals in phosphorus atoms, how the ionic radius of O2- is known, commonalities between Neon and other ions, the order of halide ionic radii, and atomic radii of pairs of elements. The questions are intended to facilitate peer instruction on open educational resources about periodic table trends.

1. Trends in the Periodic Table

2. Why share questions?
• There are many excellent open
educational resources on the
internet.
• These include many videos of
more-or-less traditional university
lecturing.
• These questions have been
provided on a CC-BY basis to
facilitate peer instruction.

3. How many quantum numbers are required
to define the highest energy occupied
orbitals in phosphorus atoms?
A. 1
B. 2
C. 3
D. 4
1
2
3
4
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4. How do we know the ionic radii of O2− is
1.40 Å?
A. Distance measurements
of compounds with
oxygen and a more
electronegative element
B. Halving the O2 bond
length
C. Distance measurements
of lattices with oxygen
and a more
electropositive element
D. From the atomic radius
of isoelectric Ne.
A. B. C. D.
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5. What do the ions O2-, F- Na+ and Mg2+
have in common with atomic Neon (Ne)?
A. Pretty Colours?
B. Similar radii?
C. High solubility in
water?
D. They have the same
number of electrons?
Pretty
Colours?
Sim
ilarradii?
High
solubilityin
w
ater?
They
have
the
sam
e
num
ber...
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6. Which of these is the correct order for the
ionic radii of the halide ions?
A. I- > F- > Br- > Cl-
B. I- < Br- < Cl- < F-
C. Li+ < Na+ < K+ < Rb+ <
Cs+
D. F- < Cl- < Br- < I-
I->
F->
Br->
Cl-
I-<
Br-<Cl-<
F-
Li+
<
Na+
<
K+
<
Rb+
<
Cs+
F-<
Cl-<
Br-<
I-
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7. Which of the following pairs of elements
are closest in atomic radii?
A. Carbon and
Phosphorus
B. Nitrogen and Silicon
C. Bromine and Barium
D. Carbon and Silicon
Carbon
and
PhosphorusNitrogen
and
SiliconBrom
ine
and
Barium
Carbon
and
Silicon
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