1. Draw all 4 positional isomers of ethylmethyl cyclohexane and its all possible stereoisomers, include R or S 2. Draw any stereoisomer (trans) of that conformer in a chair conformer, draw its flipped too

Consider the Newman projection below. a. Draw a full Lewis structure of this molecule with R1=Me,R2=Et , and R3=iPr . b. Given the sizes of these R groups (R3R2R1) , does the Newman projection above show thelowest potential energy conformation of this bond? If not, draw a Newman projectionshowing the lowest P.E. conformation (sighting down this same bond). c. To draw a Newman projection in the lowest P.E. conformation, the following rule of thumbusually applies: Place the largest group on the front carbon anti to the largest group on theback carbon. Is your answer to the previous question consistent with this rule of thumb?

Fill in the blanks: cis-1,3-Dimethylcyclohexane has two different chair conformations: one withboth methyl groups in __________ positions and one with both methyl groups in ____________ positions.

Following is a planar hexagon representation for one isomer of 1,2,4-trimethylcyclohexane. Draw the alternative chair conformations of this compound and state which of the two is more stable.