Question

1. use the periodic table to choose the best answer. which of these is the correct lewis structure for $nh_3$? lewis structure options as shown in the image

Explanation:

1. Nitrogen (N) has 5 valence electrons. Each hydrogen (H) has 1 valence electron, so 3 H atoms contribute 3 valence electrons, for a total of $5+3=8$ valence electrons in $\text{NH}_3$.
2. Nitrogen forms single covalent bonds with each of the 3 H atoms, using 6 of the 8 valence electrons (3 bonds × 2 electrons per bond).
3. The remaining 2 valence electrons exist as a lone pair on the nitrogen atom, satisfying the octet rule for N and duet rule for H.
4. The first option has incorrect double bonds, the second includes an oxygen atom not present in $\text{NH}_3$, and the third lacks the lone pair on N.

Answer:

D. $\boldsymbol{\ce{H - \underset{\Large{\boldsymbol{\cdot \cdot}}}{N} - H\\ \quad \mid\\ \quad H}}$