Well, again it is better to play around with pencil, and paper to draw out an organic formula … but we will make a trial here …. first off, we draw the nonane backbone, i.e. C9H20 …
And then we substitute at C4 with an ethyl group, and at C3 , and C5 with methyl groups…
But please try this out on paper … because the unambiguous representation of chemical formulae is VITAL for success in organic chemistry. And which carbons here are stereocentres…?
