Which of the following compounds contains a coordinate covalent bond?

• A. H2O
• B. NaCl
• C. O2
• D. NH4+

Answer: (D)

Verified step by step guidance

1. Understand what a coordinate covalent bond (also called a dative bond) is: it is a type of covalent bond where both electrons in the shared pair come from the same atom, rather than one electron from each atom.
2. Analyze each compound given in the problem to determine if it contains a coordinate covalent bond:
3. For H2O (water), the bonds are regular covalent bonds where oxygen shares electrons with hydrogen atoms, each contributing one electron.
4. For NaCl (sodium chloride), the bond is ionic, formed by the transfer of electrons from sodium to chlorine, not a coordinate covalent bond.
5. For O2 (oxygen gas), the bond is a double covalent bond with electrons shared equally between the two oxygen atoms, not a coordinate covalent bond.
6. For NH4+ (ammonium ion), the nitrogen atom donates a lone pair of electrons to bond with an additional hydrogen ion (H+), forming a coordinate covalent bond.