3.2.1.0: Trends in Size (Problems)
- Page ID
- 210694
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PROBLEM \(\PageIndex{1}\)
Based on their positions in the periodic table, predict which has the smallest atomic radius: Mg, Sr, Si, Cl, I.
- Answer
-
Cl
PROBLEM \(\PageIndex{2}\)
Based on their positions in the periodic table, predict which has the largest atomic radius: Li, Rb, N, F, I.
- Answer
-
Rb
PROBLEM \(\PageIndex{3}\)
Based on their positions in the periodic table, list the following atoms in order of increasing radius: Cs, Ca, Rb, Mg
- Answer
-
Mg < Ca < Rb < Cs
PROBLEM \(\PageIndex{4}\)
Based on their positions in the periodic table, list the following atoms in order of increasing radius: Sr, Cl, Ca, Si.
- Answer
-
Cl < Si < Ca < Sr
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PROBLEM \(\PageIndex{5}\)
Based on their positions in the periodic table, list the following ions in order of increasing radius: K+, Ca2+, Al3+, Si4+.
- Answer
-
Si4+ < Al3+ < Ca2+ < K+
PROBLEM \(\PageIndex{6}\)
List the following ions in order of increasing radius: Br–, Li+, Te2–, Mg2+.
- Answer
-
Li+ < Mg2+ < Br– < Te2–
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PROBLEM \(\PageIndex{7}\)
Which atom and/or ion is (are) isoelectronic with Br+: Se2+, Se, As–, Kr, Ga3+, Cl–?
- Answer
-
Se, As−
PROBLEM \(\PageIndex{8}\)
Which of the following atoms and ions is (are) isoelectronic with S2+: Si4+, Cl3+, Ar, As3+, Si, Al3+?
- Answer
-
Si, Cl3+
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PROBLEM \(\PageIndex{9}\)
Compare both the numbers of protons and electrons present in each to rank the following ions in order of increasing radius: As3–, Br–, K+, Mg2+.
- Answer
-
Mg2+ < K+ < Br– < As3–
PROBLEM \(\PageIndex{10}\)
The ionic radii of the ions S2–, Cl–, and K+ are 184, 181, 138 pm respectively. Explain why these ions have different sizes even though they contain the same number of electrons.
- Answer
-
They have different numbers of protons, which determines their size.
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Contributors and Attributions
Paul Flowers (University of North Carolina - Pembroke), Klaus Theopold (University of Delaware) and Richard Langley (Stephen F. Austin State University) with contributing authors. Textbook content produced by OpenStax College is licensed under a Creative Commons Attribution License 4.0 license. Download for free at http://cnx.org/contents/85abf193-2bd...a7ac8df6@9.110).
- Adelaide Clark, Oregon Institute of Technology
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