Do carbon-hydrogen compounds react with permanganate?
These will be discussed in Week 13 lecture. 5.26d Vitamin A has many C=C bonds, so it is expected to react with permanganate. 5.27 What is the geometry of double bonded molecules? (a) This will be discussed in Week 13 lecture. The molecular geometry at the central atoms is trigonal planar. (b) The bond angles in the real molecules are actually ~120, but because the models were made from tetrahedral model kit centers, the angles in the models are closer to 109C. (We will learn to make models using kit pieces that give the correct 120 geometry later in the text.) (c) The C-C bond length in ethane is a little longer than the C=C bond in ethane. You can see this in the two models if you use the curved connectors to represent the double bond and a white connector for the C-C single bond. There are more bonding e- in C=C vs. C-C, and they draw the two nuclei closer together. (d) A C-O bond is shorter than a C-C bond because of the smaller size of O vs. C (bond length depends on atom size). 5
