2.2: The Structure of the Atom and How We Represent It (Problems)
- Page ID
- 98687
PROBLEM \(\PageIndex{1}\)
In what way are isotopes of a given element always different? In what way(s) are they always the same?
- Answer
-
They always have different masses due to different numbers of neutrons.
They always have the same number of protons (which determines the identity).
PROBLEM \(\PageIndex{2}\)
Write the symbol for each of the following ions:
(a) the ion with a 1+ charge, atomic number 55, and mass number 133
(b) the ion with 54 electrons, 53 protons, and 74 neutrons
(c) the ion with atomic number 15, mass number 31, and a 3− charge
(d) the ion with 24 electrons, 30 neutrons, and a 3+ charge
- Answer a
-
\(\ce{^{133}_55Cs}\)+
- Answer b
-
\(\ce{^{127}_53I}\)-
- Answer c
-
\(\ce{^{31}_15P}\)3-
- Answer d
-
\(\ce{^{57}_27Co}\)3+
PROBLEM \(\PageIndex{3}\)
Write the symbol for each of the following ions:
(a) the ion with a 3+ charge, 28 electrons, and a mass number of 71
(b) the ion with 36 electrons, 35 protons, and 45 neutrons
(c) the ion with 86 electrons, 142 neutrons, and a 4+ charge
(d) the ion with a 2+ charge, atomic number 38, and mass number 87
- Answer a
- \(\ce{^{71}_31Ga}\)3+
- Answer b
-
\(\ce{^{80}_35Br}\)-
- Answer c
-
\(\ce{^{232}_90Th}\)4+
- Answer d
-
\(\ce{^{87}_38Sr}\)2+
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Contributors
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