The chlorate ion, ClO3−, is often depicted with the chlorine atom single-bonded to three oxygen atoms. A partially completed diagram showing only the Cl–O sigma bonds is supplied.
(1) Complete the Lewis diagram by adding all lone-pair electrons necessary on every atom so that the arrangement reflects a plausible structure for ClO3−. Be sure to enclose the structure in brackets and include its charge.
(2) Calculate the formal charge of the chlorine atom and of each oxygen atom in the completed structure.
(3) Using your results, determine the total number of equivalent resonance structures that can be drawn without altering the connectivity of atoms in ClO3−. Justify your answer in terms of the distribution of formal charges.