Question

This phenomenon is used to cleave a ketone and abstract a gamma hydrogen to make a substituted cyclobutane in the Yang reaction. This phenomenon must be utilized to form cyclobutadiene (“cyclo-buta-di-ene”) in a pericyclic manner, since it’s otherwise (10[1])spin-forbidden per the (10[1])Woodward–Hoffmann rules. Either this phenomenon (10[1])or another represented by a capital delta are used to promote homolysis (“huh-MALL-uh-sis”) of small molecules, such as in the first step of allylic bromination. Reaction diagrams will typically represent this phenomenon with the letters “h nu” above (10[1])the reaction arrow. (10[3]-5[1])Compounds that decompose due to this phenomenon, such as hydrogen peroxide, are typically kept (10[1])in opaque or brown bottles. For 10 points, reactions involving what phenomenon are studied in photochemistry? ■END■ (10[1])

ANSWER: light [or photons; accept sunlight; accept radiation; accept UV light or UV radiation; prompt on energy by asking “in what form?”]
<Chemistry>
= Average correct buzz position

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Buzzes

PlayerTeamOpponentBuzz PositionValue
Richard NiuCornell CYale A3610
Srikar VenkatesanPenn BRutgers B3910
Vishal KanigicherlaPenn AColumbia A4410
Arjun BothraHaverfordVassar8110
Rico-ian BantingNYU BBard A8410
Dylan Epstein-Gross (DII)Princeton ARowan A8410
Andrew MinagarYale BColumbia B8410
Iyanu NafiuYale CPrinceton B84-5
Aiden DartleyRutgers ANYU A9810
Jupiter DingPrinceton BYale C11510

Summary

2023 ACF Winter @ Columbia11/11/2023Y9100%0%11%73.89