Hydrogen halides HX (where X is a halogen) exhibit a wide range of bond energies. The following data are given for one member of the series:
Bond H–Cl
Bond length 127 pm
Bond energy 431 kJ mol⁻¹
The atomic radii of the halogens are listed below:
F 64 pm Cl 99 pm Br 114 pm I 133 pm
Answer the questions that follow.
(a) Using only the information provided above and general principles of chemical bonding, develop a logically argued estimate (not a mere guess) for the bond length of the H–F bond. Show all reasoning steps.
(b) Using your estimate from part (a), construct a reasoned prediction for the bond energy of the H–F bond. Your argument should explicitly connect bond length to bond energy.
(c) Discuss at least two assumptions or simplifications inherent in your reasoning in parts (a) and (b), and evaluate how each assumption could affect the accuracy of your predictions.
(d) Suggest one experimental technique that could be used to test the accuracy of your predicted H–F bond length or bond energy, and briefly explain what observable would be measured.