1.Not all chiral molecules are required to have an individual atom that is chiral. For example, the allene below is chiral and optically active without a chiral carbon. Explain how this is the case and be sure to use a drawing to support your logic. HINT: Think about the orbitals and implication of their orientation. (5 points) Write your answer on a blank piece of paper to give us space to see what you write when we grade. Answers squeezed into small spaces or un-readable will be given an instant zero from this point on. 2. Provide an acceptable IUPAC name for the following molecules. Spelling and formatting are graded. (5 points) 3. For each set of molecules, identify the best nucleophile. For part c, circle the most nucleophilic atom. (3 points)

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.