Ch.8 - Periodic Properties of the ElementsWorksheetSee all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds

Solution: In the ionic compounds LiF, NaCl, KBr, and RbI, the measured cation-anion distances are 2.01 Å (Li–F), 2.82 Å (Na–Cl), 3.30 Å (K–Br), and 3.67 Å (Rb–I), respectively.What estimates of the cation–anion distance would you obtain for these four compounds using neutral atom bonding atomic radii? Are these estimates as accurate as the estimates using ionic radii?

Problem
In the ionic compounds LiF, NaCl, KBr, and RbI, the measured cation-anion distances are 2.01 Å (Li–F), 2.82 Å (Na–Cl), 3.30 Å (K–Br), and 3.67 Å (Rb–I), respectively.
Period 2 Group 1A contains Li 1.28 and Li cation 0.90.  Period 3 Group 1A Na 1.66 and Na+ 1.16.  Period 3 Group 1A K 2.03 and K+ 1.52.  Period 4 Group 1A Rb 2.20 and Rb+ 1.66.Period 1 Group 2A contains Be 0.96 and Be2+ 0.59.  Period 2 Group 2A contains Mg 1.41 and Mg2+ 0.86. Period 3 Group 2A contains Ca 1.76 and Ca2+ 1.76.  Period 4 contains Sr 1.95 and Sr2+ 1.32. Period 1 Group 3A contains B 0.84 and B3+ 0.41.  Period 2 Group 3A contains Al 1.21 and Al3+ 0.68.  Period 3 contains Ga 1.22 and Ga3+ 0.76.  Period 4 contains In 1.42 and In3+ 0.94. Period 1 Group 6A contains O 0.66 and O2- 1.26. Period 2 Group 6A contains S 1.05 and S2- 1.70. Period 3 contains Se 1.20 and Se2- 1.84.  Period 4 Te 1.38 and Te2- 2.07. Period 1 Group 7A contains F 0.57 and F- 1.19.  Period 2 Group 7A contains Cl 1.02 and Cl- 1.67.  Period 3 contains Br 1.20 and Br- 1.82.  Period 4 I 1.39 and I- 2.06.
What estimates of the cation–anion distance would you obtain for these four compounds using neutral atom bonding atomic radii? Are these estimates as accurate as the estimates using ionic radii?