Determine if the structures below are valid or invalid ionic Lewis structures.

Identify which one of the following XO₃ ions has an expanded octet (more than eight electrons) on the central atom.

Provide the Lewis structure for PBr₅.

a. What is the Lewis structure for SF₅^-?
b. Does SF₅^- follow the octet rule? If not, which atom does not follow?
c. How many electrons surround each atom in SF₅^-?

Arsenic (III) oxide (As₂O₃) reacts with water to form arsenous acid (H₃AsO₃). Draw the Lewis structure of arsenous acid that obeys the octet rule.

Draw the correct Lewis structure for HNO₃ that satisfies the octet rule

Using formal charges, identify the resonance structure that contributes the most to the hybrid.

Give all the possible resonance structures (some will not obey the octet rule) for N₂O₄ (O₂NNO₂). Show the curve arrows to represent the conversion of one structure to another.

1. For the structure below, draw a second resonance form:

2. For the structure below, draw a second resonance form:

3. For the structure below, draw a second resonance form:

Is the C—C bond stronger between C₂H₄ or C₂H₆? Explain.

Which of the following would have the longest C–O bonds?