Which of the following statements correctly describes the Lewis dot structure of neutral HNO2 (nitrous acid)?

• A. The central nitrogen atom is bonded to two oxygen atoms, both with double bonds, and no hydrogen atom is attached.
• B. The central nitrogen atom is bonded to two hydrogen atoms and one oxygen atom.
• C. The central nitrogen atom is bonded to two oxygen atoms and one hydrogen atom, with one oxygen having a double bond and the other a single bond plus a hydrogen.
• D. The central nitrogen atom is bonded to three oxygen atoms, with one oxygen also bonded to a hydrogen atom.

Answer: (C)

Verified step by step guidance

1. Step 1: Identify the total number of valence electrons in HNO2. Hydrogen (H) has 1 valence electron, nitrogen (N) has 5, and oxygen (O) has 6 each. Since there are two oxygens, calculate the total as: \$1 + 5 + 2 \times 6 = 18$ valence electrons.
2. Step 2: Determine the central atom, which is usually the least electronegative element that can form multiple bonds. Here, nitrogen (N) is the central atom bonded to two oxygen atoms.
3. Step 3: Connect the atoms with single bonds initially: N bonded to two O atoms, and one of the O atoms bonded to a hydrogen atom. This accounts for some of the valence electrons used in bonding.
4. Step 4: Distribute the remaining valence electrons to satisfy the octet rule for each atom. One oxygen will form a double bond with nitrogen to complete its octet, while the other oxygen is single bonded to nitrogen and also bonded to hydrogen, completing its octet with lone pairs.
5. Step 5: Confirm that the total number of electrons used in bonds and lone pairs equals the total valence electrons (18), and that the structure reflects the correct bonding: nitrogen bonded to two oxygens (one double bond, one single bond plus hydrogen).