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Draw the skeletal structure for the following compound: $$\ce{HOCH2CH2OCH2C#CCH2CH(CH3)2}$$

I can't figure this out.

I can draw it up until the triple bond. My professor marked off because the triple bond was not drawn correctly.

So, is the triple bond depicted any differently from the other bonds in the molecule? If so, why?

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    $\begingroup$ If you show us what you drew, then perhaps we can tell you where you went wrong? My guess is you forgot to include the linear nature of the $sp$ carbon-carbon bonds ;) $\endgroup$ – paracetamol Sep 13 '17 at 16:58
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My guess, is that you forgot to take the linear disposition of the carbon-carbon triple bonds into consideration.

So the bond lines cutting through four carbon atoms will be linear, and not zig-zagged as in the rest of the molecule (the latter implies tetrahedral geometry accorded by the $sp^3$ carbon-carbon bonds)

What you probably drew:

enter image description here

As opposed to what the skeletal representation for your molecule is supposed to look like:

enter image description here

Crude diagram courtesy: MS Paint application

Okay, it might be better if you draw the whole thing with the (lone) triple bond parallel to the bottom of your page (i.e- aligned with the horizontal)

The first diagram may feel more "graceful" (the term I used when I defended my incorrect depiction of the triple bond to my teacher when he asked me a similar question a while back), but it is incorrect.

The red circles represent the carbon atoms in your molecule. They (red-carbon-circles) aren't supposed to be drawn in, but I added it for clarity O:)

Also, our veteran organic + inorganic chemist, user @Jan, provides us some insight on the alignment of the triple bond:

Unless the triple bond is the most significant structural feature (which it is not here) I would not align it horizontally or parallel to the bottom of the page.


P.S-

If it makes you feel any better, I had to draw and re-draw the (correct) skeletal representation of your molecule a few times before I got it right.

Kudos to your professor for the good question! ;)

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    $\begingroup$ Unless the triple bond is the most significant structural feature (which it is not here) I would not align it horizontally or parallel to the bottom of the page. The way you drew it looks better to me. $\endgroup$ – Jan Sep 14 '17 at 4:54

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