In a straight-chain (unbranched) alkane, each carbon atom is joined to no more than two other carbon atoms.The first ten straight-chain alkanes are methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane and decane, with 1 to 10 carbon atoms.The chain is not actually straight. The tetrahedral bond angle of 109.5° around each carbon gives the chain a zigzag shape, which is why skeletal formulae are drawn as zigzags.
Because there are single bonds, the groups can rotate freely about each C-C bond, so the chain is flexible.
Because there are single bonds, the groups can rotate freely about each C-C bond, so the chain is flexible.