. How many stereoisomers are formed in this Diels-Alder reaction ? Explain why. 2. Identify the Diene and the dienophile in the reaction. 3. The MW of the expected product is 319.4 g/mol. However, the mass spectrometry analysis produces a peak at 320.4 g/mol. Explain why the MS analysis differs in 1 amu as compared to the product formed. 4. Give two significant signals that you would expect to see in the IR spectra of the final product. 5. Why is this procedure considered a green chemistry reaction ? 6. From the given 1H-NMR spectra, provide an explanation for the multiplicity and chemical shift of the following signals: a) CH3 20 (blue in the spectra, singlet, d=2.5 ppm) b) CH 16 (blue in the spectra, doublet, d=4.75 ppm) c) CH 15 (yellow in the spectra, doublet, d=5.1ppm)

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.