Which of the following molecules is capable of forming hydrogen bonds?

• A. CO2
• B. NH3
• C. C2H6
• D. CH4

Answer: (B)

Verified step by step guidance

1. Understand the concept of hydrogen bonding: Hydrogen bonding occurs when a hydrogen atom is covalently bonded to a highly electronegative atom such as nitrogen (N), oxygen (O), or fluorine (F), and this hydrogen is attracted to a lone pair of electrons on another electronegative atom in a nearby molecule.
2. Examine each molecule to identify if it contains hydrogen atoms bonded to N, O, or F:
3. For \(\mathrm{CO_2}\): Carbon dioxide has no hydrogen atoms, so it cannot form hydrogen bonds.
4. For \(\mathrm{NH_3}\) (ammonia): Nitrogen is bonded to hydrogen atoms, and nitrogen is highly electronegative with lone pairs, so \(\mathrm{NH_3}\) can form hydrogen bonds.
5. For \(\mathrm{C_2H_6}\) (ethane) and \(\mathrm{CH_4}\) (methane): Both contain only carbon and hydrogen, and carbon is not electronegative enough to create hydrogen bonding, so these molecules cannot form hydrogen bonds.