CHM 230 Final Exam Questions With Complete Solutions

A saturated hydrocarbon is correct answer: an alkane Which molecule below has the highest boiling point? correct answer: Butanol Which molecule below is least soluble in water? correct answer: butane- one without any functional groups Cis/trans isomer ratios were important in European corn borer moths because correct answer: A, C & D- Specific ratios of cis to trans are used as pheromones by the moths- The ratios help male moths locate female moths for breeding purposes- The ratios may be different depending on where moths are geographically Many long alkenes in nature are found to be composed of correct answer: isoprene units Which bond below is the least polar? correct answer: C-H H C N Cl O F 2.1 2.5 3.0 3.0 3.5 4.0 The intermolecular force that is most important in explaining the solubility of alcohols in water is correct answer: hydrogen bonding The scientist credited with determining the resonance structure of benzene is correct answer: pauling The major component in natural gas is correct answer: methane The carboxyl group (C=O) is not found in (or is not part of) the functional group correct answer: ethers Which water molecule is correctly depicted as hydrogen bonding to the molecule below correct answer: C- H-O-H Which of the following exhibits cis-trans isomerization? correct answer: a) 1-pentene b) 2-pentene c) 2-methyl-1-butene d) 2-methyl-2-butene e) 2-methyl-2-pentene B Branching in alkanes correct answer: raises boiling point Double bonds correct answer: lowers boiling point Benzene belongs to which family of organic compounds? correct answer: Aromatic Which intermolecular force is most important in explaining the solubility of 2-octanol in hexane? correct answer: london dispersion forces The dehydration of 1-butanol primarily forms correct answer: H2O and 1-butene Dehydration of phenols correct answer: NO REACTION The compound germacrene has how many isoprene units? correct answer: 3 Monoterpenes correct answer: 2 isoterpene units C10H16 Sesquiterpenes correct answer: 3 isoterpene units C15H24 Diterpenes correct answer: 4 isoterpene units C20H32 triterpenes correct answer: 6 isoterpene units C30H48 Tetraterpenes correct answer: 8 isoprene units C40H64 Which is not a user a pheromone by insects or mammals? correct answer: Used to lower body temp during hiberation Which of the following molecules is chiral? correct answer: a) 1-pentanol b) 2-pentanol c) 3-pentanol d) cyclopentanol B What is the max number of stereoisomers for a molecule with 4 stereo centers? correct answer: 16 2^n -- 2^4=16 When the notation (-) is used for an optically active compound, it means which of the following? correct answer: The compound rotates plane-polarized light to the left