For the neutral molecule NH3, how many lone pairs of electrons should be added to complete its Lewis dot structure?

• A. 1 lone pair
• B. 3 lone pairs
• C. 0 lone pairs
• D. 2 lone pairs

Answer: (A)

Verified step by step guidance

1. Determine the total number of valence electrons for the molecule NH3. Nitrogen (N) has 5 valence electrons, and each hydrogen (H) has 1 valence electron, so calculate the sum: \$5 + 3 \times 1$.
2. Draw the skeletal structure of NH3 with nitrogen as the central atom bonded to three hydrogen atoms using single bonds. Each bond represents 2 electrons.
3. Subtract the electrons used in bonding from the total valence electrons to find the remaining electrons that will be placed as lone pairs.
4. Place the remaining electrons as lone pairs on the central nitrogen atom to complete its octet, remembering that hydrogen atoms only need 2 electrons each.
5. Count the number of lone pairs on the nitrogen atom after placing the remaining electrons to complete the Lewis dot structure.