Draw all the structural isomers (number of isomers in parenthesis) for the following chemical formulas:

(1) CHF₃

(1) C₂H₃Cl

(2) C₃H₇Cl

(2) C₂H₆O

(3) C₃H₈O

(7) C₄H₁₁N

(4) C₂H₅N

(6) C₂H₃OF