Topic 2A: Bonding: แบบฝึกหัด

Which of the following describes the bonding in a molecule of carbon dioxide, \(CO_{2}\)?

The boiling temperatures of the hydrogen halides follow the trend: \(HF > HI > HBr > HCl\). Which of the following best explains why \(HF\) has the highest boiling temperature?

Which of the following molecules has a bond angle of approximately \(107^{\circ}\)?

Explain, in terms of structure and bonding, why the boiling temperature of hydrogen fluoride (\(HF, 293\) K) is significantly higher than that of hydrogen chloride (\(HCl, 188\) K).

Using electron-pair repulsion theory, predict the shape and the bond angle of the ammonia molecule, \(NH_{3}\).

The table below provides the boiling temperatures for three compounds with similar numbers of electrons:

\( CH_{3}CH_{2}CH_{2}CH_{3} \) (Butane): 272 K
\( CH_{3}CH_{2}CHO \) (Propanal): 322 K
\( CH_{3}CH_{2}CH_{2}OH \) (Propan-1-ol): 370 K

(a) Identify the primary intermolecular force present in each substance.
(b) Explain the trend in boiling temperatures in terms of the strength of these intermolecular forces and the structure of the molecules.
(c) Predict the shape and the bond angle around the central carbon atom in the carbonyl group of propanal using electron-pair repulsion theory.