Question

Description acceptable. Brassard’s and Rawal’s dienes favor atoms with high values of this property in variants of the Diels–Alder reaction. Reactions that favor high values of this property are driven by higher values of the heat of hydrogenation. A rule favoring higher values of this property is subverted via exhaustive methylation of a nitrogen (10[1])atom during one elimination. (10[1]-5[1])Carbocations settle (10[1])on atoms with a local maximum (10[1])of this property (10[2])to terminate repeated alkyl or hydride shifts. Stabilization of carbocations by hyperconjugation (-5[1])allow SN1 reactions to dominate SN2 at atoms with high values (10[2]-5[1])for this property. (10[1])This (-5[1])property directs the (-5[1])regio·selectivity of Zaitsev’s (-5[1])rule for alkene-forming (10[1]-5[1])eliminations and Markovnikov’s rule for additions. For (10[1])10 points, describe this property that differentiates primary, (10[1])secondary, (10[1])tertiary, (10[1]-5[1])and quaternary atoms. ■END■ (10[5]0[5])

ANSWER: degree of substitution [accept answers describing how many R groups, substituents, other groups, or other (non-hydrogen) atoms an atom is bonded to; accept answers describing whether an atom is primary or secondary or tertiary or quaternary until read; prompt on answers involving steric effects or steric bulk]
<Chemistry>
= Average correct buzz position

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Summary

2025 ACF Nationals04/19/2025Y2383%0%35%97.16

Buzzes

PlayerTeamOpponentBuzz PositionValue
Liam KusalikWaterloo AStanford5310
Adam FineChicago AIllinois A57-5
Anurag SodhiMITVirginia Tech5710
Karan GurazadaTexasToronto B5910
Joy AnHarvardChicago B6510
Bryan UgazArizona StateYale6810
Richard NiuCornell AJohns Hopkins6810
Geoffrey WuColumbia AUC Berkeley A80-5
Calvin BostlemanOhio StateMaryland9110
Shiva TegullaUCFIllinois B9110
Russell NipBritish ColumbiaWaterloo B91-5
Rasheeq AzadNorth Carolina ARutgers9410
Teigue KellyPenn StateLSE95-5
Amogh KulkarniGeorgia StateFlorida98-5
Sharath NarayanNorthwesternIndiana101-5
Tony ChenToronto AWUSTL A104-5
June YinWUSTL BNYU10410
Derek ChenColumbia BWinona State11110
Rohan DalalGeorgia TechIowa State11910
Jason ZhangToronto CMinnesota12010
James WangOttawaUC Berkeley B12110
Rachel FanousMichiganRIT121-5
Rohan ShelkeUC Berkeley AColumbia A12510
Tiffany ZhouFloridaGeorgia State1250
Andrew WangIllinois AChicago A12510
Alex AkridgeIndianaNorthwestern12510
Soren HeydariNorth Carolina BCornell B1250
Yared TadesseCornell BNorth Carolina B1250
Albert Yingzhi NyangLSEPenn State1250
Cade ReinbergerRITMichigan1250
Neal JoshiWUSTL AToronto A12510
Caleb OttWaterloo BBritish Columbia12510