Can't name these organic compounds!Watch
B) is a branched alkane and has no other groups. The backbone consists of 7 carbon atoms so is based on heptane. Methyl groups occur on the 2nd, 4th and 5th carbon, so its therefore called 2,4,5-trimethylheptane.
C) is a cycloalkene. It is made up of 5 carbons so is based on pentene. Double bonds occur after the 1st and 3rd carbon, so its name is 1,3-cyclopentadiene.