Tools of the trade: 3-dimensional structures
Organic compounds are 3‐dimensional and their shape depends on the preferred spatial arrangement of the covalent bonds. The shape of organic compounds are best viewed with the aid of molecular models.
The structure gets more complicated for larger molecules. For butanal, like for methane, we see that three carbon atoms have a tetrahedral shape, but the one in the aldehyde functional group (the purple carbon) is different. It has a trigonal planar, or flat, shape – with the aldehyde carbon in the centre, and oxygen, hydrogen and another carbon pointing to the corners of an equilateral triangle. The bond angles are 120°.
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