How many distinct constitutional isomers are possible for the molecular formula $C_2{\mathrm{Cl}}_3{F}_3$?

Classify the following pair of compounds: $C_4{H}_{10}$ (butane) and $C_4{H}_{10}$ (2-methylpropane). Select the single best answer.

Given the following set of structural formulas, how many different constitutional isomers are represented?

Which of the following pairs are constitutional isomers of $C_2{H}_6{O}_2$?

Which of the following statements is correct regarding the constitutional isomers of $C_5{H}_{12}$?

Which of the following pairs are constitutional isomers of $C_2{H}_3{\mathrm{Cl}}_3$?

Which of the following pairs of compounds are constitutional isomers?

Which pair of the following compounds are constitutional isomers?

Given the following pair of structures, indicate the relationship between them: Structure 1: $C_4{H}_{10}$ (n-butane) and Structure 2: $C_4{H}_{10}$ (isobutane).