Organic Chemistry

Learn the toughest concepts covered in Organic Chemistry with step-by-step video tutorials and practice problems by world-class tutors.

4. Alkanes and Cycloalkanes

Barrier To Rotation

Next Topic

Sometimes we’ll be asked to actually calculate the amount of energy a Newman Projection “spends” while rotating. 

Important Barrier of Rotation Values

1

concept

4 Values You Should Memorize

clock
2m
Play a video:
Was this helpful ?
0
Content

These are the values we’ll need so we can solve for the unknown interactions in these questions. 

2

example

Determining energy cost of eclipsed interaction

clock
3m
Play a video:
Was this helpful ?
0

Now it’s time to put your knowledge to the test. Remember to draw the eclipsed version to know what the interactions are!

3
Problem

The barrier to rotation for 1,2 -dibromopropane along the C1—C2 bond is 28 kJ/mol. Determine the energy cost associated with the eclipsing dibromine interaction.