Question

A form of solution-phase Raman spectro·scopy named for this molecular property reports a value called C·I·D. This quantity is unexpectedly zero for the molecule N-butyl·ethyl-N-hexyl-N-propyl·methane. Greater values for this property of a cholesteric (“COAL-uh-steer-ick”) mesogen allow proportionally thinner films to be used in LCDs. Food scientists measure this property as a quality check on the concentration of sugar in syrup. (-5[2])This quantity is traditionally reported at the sodium D line, but since it’s the Kramers–Kronig transform of ellipticity, its dispersion is reported by circular di·chroism. Specific (10[1]-5[1])values for this quantity are symbolized by an alpha (-5[1])in (10[1])brackets. (-5[1])To indicate the (10[1])sign (10[1])of this quantity, (10[1])IUPAC (“I-U-pack”) now prefers pluses and minuses to the archaic (-5[1])prefixes (-5[1])D and L. (10[1]-5[3])For 10 points, enantio·meric (-5[1])excess (-5[1])is calculated by using a polarimeter to measure what angle, (-5[1])which is only nonzero for chiral molecules? (10[2])■END■ (10[4]0[5])

ANSWER: optical rotation [or OR; or specific optical rotation angle; or specific rotation angle; or optical activity or specific optical activity; or OA; or optical rotatory power; or optical rotatory dispersion or ORD; accept any answer that indicates a change OR difference OR rotation in the polarization of polarized light; prompt on rotation; reject “chirality”; reject “chiral angle”; reject “polarization” without any explicit indication of a change or difference]
<Chemistry>
= Average correct buzz position

Summary

2023 ACF Nationals04/22/2023Y2060%0%65%118.17

Buzzes

PlayerTeamOpponentBuzz PositionValue
Karan GurazadaTexas AMIT A58-5
Sharath NarayanNorthwestern AHarvard A58-5
Shahar SchwartzUC Berkeley ACornell B8410
Daniel MaYale AGeorgia Tech A84-5
Paul LeeWUSTL AChicago B93-5
Adam FineChicago AStanford A9410
Vittal BhatNorth Carolina AToronto A95-5
Neal JoshiWUSTL BPenn A9810
Jacob EgolDuke AFlorida A9910
Maxwell YeMinnesota AColumbia A10210
Gideon KpurubuVanderbilt ANYU A111-5
Anuttam RamjiUC Berkeley BHouston A112-5
Frederick Rivas-GiorgiYale BVirginia A115-5
Michael MaysImperial AMinnesota B115-5
Alex AkridgeIndiana AChicago C11510
Ameya PhadnisRutgers BMichigan A115-5
Tiffany ZhouFlorida BColumbia B119-5
Pranav SivaramOhio State AMaryland A120-5
Jacob Van OorschotMcGill AIllinois A130-5
Mazin OmerHarvard ANorthwestern A13710
Arya KarthikGeorgia Tech AYale A13710
JD KrothIowa State AGeorgia Tech B1380
Keegan MartinNYU AVanderbilt A13810
Todd MaslykMichigan ARutgers B1380
Raymond ChenToronto ANorth Carolina A1380
Steven LiuMIT ATexas A13810
S. A. ShenoyGeorgia Tech BIowa State A1380
Forrest WeintraubColumbia BFlorida B13810
Vivek SasseChicago BWUSTL A13810
Isaac MammelMaryland AOhio State A1380