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[Dennisse Diaz 1D]

Can someone please help explain parts a) b) c) of this question?

[Chem_Mod]

Can you explain what the question is and what you understand of it so far?

[jessicasam]

The question is: "Structural isomers are molecules that have the same formula but in which the atoms are connected in a different order. Two isomers of disulfur difluoride, S2F2, are known. In each the two S atoms are bonded to each other. In one isomer each of the S atoms is bonded to an F atom. In the other isomer, both F atoms are attached to one of the S atoms. (a) In each isomer the S-S bond length is approximately 190 pm. Are the S-S bonds in these isomers single bonds, or do they have some double bond character? (b) Draw two resonance structures for each isomer. (c) Determine for each isomer which structure is favored by formal-charge considerations. Are your conclusions consistent with the S-S bond lengths in the compounds?"

a) If you draw the two structures, you will see that both of them have resonance forms. This means that some of the bonds are double bonds and some of them are single. This would make each of the bonds a little more than a single bond. So yes, they have some double bond character.

b) You have to draw the two resonance forms based on the directions. In both, S is bonded to another S. In one, both Fs are bonded to one S. In the other, one F is bonded to one S and the other F is bonded to the other S.

c) From your Lewis Structures in part b, you can see that there is resonance occurring so you are correct to say that the S-S bond length is between and single and a double bond.