Final answer:
The Lewis structure for nitric acid (HNO3) includes a central nitrogen atom with sp² hybridization, forming a double bond with one oxygen and single bonds with two other oxygens, one of which carries the hydrogen atom. Resonance causes the bond lengths of the single-bonded oxygens to appear equivalent and shorter than typical single N-O bonds. The ONO bond angle is roughly 120° due to trigonal planar geometry, but may be slightly less due to asymmetric structure.
Step-by-step explanation:
To depict a Lewis structure for HNO₃ that is consistent with the given information, we recall that nitric acid has a total of five valence electrons from nitrogen, six from each of the three oxygens, and one from hydrogen, summing up to 24 valence electrons. In the structure, nitrogen is the central atom with a double bond to one oxygen (representing a shorter bond) and single bonds to the other two oxygens (one of which is longer). Resonance allows both single-bonded oxygens to have equivalent structures, with one of the oxygens carrying the extra hydrogen atom.
The hybridization of the nitrogen in HNO₃ is sp², as it forms three sigma bonds and has one lone pair. The structure follows the principle of resonance because experimental evidence suggests that the single bonds in nitrate ion appear to be equivalent and shorter than typical single N-O bonds, implying the lone pair on nitrogen is delocalized over the oxygen atoms. This delocalization explains the observed bond lengths of the NO₃ ion being shorter than a typical single bond, as described in the resonance section of the referenced material.
Predicting the ONO bond angle in HNO₃, we expect it to be approximately 120° since the arrangement around the central atom with sp² hybridization promotes a trigonal planar geometry. However, due to the presence of the lone pair on nitrogen and the fact that the molecule is not perfectly symmetrical, the actual bond angle might be slightly less than 120°.