MCAT Organic Chemistry Review 2018-2019

(singke) #1

(A) They cannot be distinguished from ^1 H–NMR alone.
A triplet and quartet are observed for ethanol, whereas a doublet and septet are
observed for isopropanol.


(B)


A   triplet and quartet are observed    for isopropanol,    whereas a   doublet and septet
are observed for ethanol.

(C)


The alcohol hydrogen    in  ethanol will    appear  within  that    region, whereas the
alcohol hydrogen in isopropanol will appear downfield of that region.

(D)


9 . Before  absorbing   an  ultraviolet photon, electrons   can be  found   in:

(A) the HOMO only.
(B) the LUMO only.
(C) both the HOMO and the LUMO.
(D) neither the HOMO nor the LUMO.


10 .    In  an  IR  spectrum,   how does    extended    conjugation of  double  bonds   affect  the absorbance
band of carbonyl (C=O) stretches compared with normal absorption?

(A) The absorbance band will occur at a lower wavenumber.
(B) The absorbance band will occur at a higher wavenumber.
(C) The absorbance band will occur at the same wavenumber.
(D) The absorbance band will disappear.


11 .    Wavenumber  is  directly    proportional    to:

(A) wavelength.
(B) frequency.
(C) percent transmittance.
(D) absorbance.


12 .    Two enantiomers will:
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