Question

question 3 of 29 (1 point) | question attempt: 1 of 5
the measured dipole moment of nh₂ch₂ch₂nh₂ is 1.83 d. which one of the following statements about 1,2 - ethanediamine is false? select the single best answer.
it exists as a mixture of anti and gauche conformations.
it exists entirely in the gauche conformation.
it exists entirely in the anti conformation.

Explanation:

1,2 - ethylenediamine ($NH_2CH_2CH_2NH_2$) exists as a mixture of anti and gauche conformations in solution due to free rotation around the $C - C$ bond. The anti - conformation has a zero dipole moment and the gauche - conformation has a non - zero dipole moment. Since the measured dipole moment is non - zero (1.83 D), it cannot exist entirely in the anti - conformation. Also, it does not exist entirely in the gauche conformation as it can interconvert between conformations.

Answer:

C. It exists entirely in the anti - conformation.