Which of the following compounds does not exhibit covalent (molecular) bonding?

• A. H_2O
• B. NaCl
• C. CO_2
• D. CH_4

Answer: (B)

Verified step by step guidance

1. Understand the difference between covalent (molecular) bonding and ionic bonding. Covalent bonds involve the sharing of electron pairs between atoms, typically between nonmetals, while ionic bonds involve the transfer of electrons from a metal to a nonmetal, resulting in oppositely charged ions held together by electrostatic forces.
2. Examine each compound to identify the types of elements involved: H_2O (hydrogen and oxygen, both nonmetals), CO_2 (carbon and oxygen, both nonmetals), CH_4 (carbon and hydrogen, both nonmetals), and NaCl (sodium, a metal, and chlorine, a nonmetal).
3. Recognize that compounds formed between two nonmetals generally exhibit covalent bonding because they share electrons to achieve stable electron configurations.
4. Identify that NaCl consists of a metal (Na) and a nonmetal (Cl), which typically form ionic bonds due to the transfer of electrons from the metal to the nonmetal, creating ions.
5. Conclude that NaCl does not exhibit covalent (molecular) bonding, unlike the other compounds listed, which are molecular and held together by covalent bonds.