Packet D: Bonus 1

In February 2025, a team led by the University of Surrey discovered an oblate spheroid nucleus for one of this element’s isotopes. For 10 points each:
[10m] Name this element whose 208-isotope is molten and mixed with bismuth as a neutron moderator material. That isotope of this element has a doubly magic nucleus and ends the thorium and actinium decay series.
ANSWER: lead [or Pb; accept lead-208 or Pb-208]
[10e] Lead-bismuth mixtures are also used as coolants in the fast type of these devices. Elevated temperatures in these devices can generate steam voids, which resulted in a meltdown of its RMBK type at Chernobyl.
ANSWER: nuclear reactor [or fission reactor; accept fast breeders; prompt on nuclear power plant or fission power plant]
[10h] A drawback of using bismuth-209 is that it can spontaneously undergo this process then beta-minus decay to form alpha-emitting polonium-210. A sensitive elemental analysis technique uses energy-dispersive XRS to induce this process.
ANSWER: neutron activation [accept neutron activation analysis or NAA; accept neutron capture or neutron absorption; prompt on activation or capture or absorption]
<Oxford A/Columbia C, Chemistry> | Packet D - UBC B, Oxford A, Waterloo B, CWRU A

HeardPPBE %M %H %
6917.10100%68%3%

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Conversion

TeamOpponentPart 1Part 2Part 3TotalParts
Alabama AMississipi State010010E
Arizona StateUCSD C1010020ME
Berkeley BBerkeley A1010020ME
Berkeley CBerkeley D1010020ME
BirminghamOxford C1010020ME
Brandeis BBrandeis A1010020ME
BrownSouthern Connecticut State1010020ME
BruinTennessee B010010E
Cambridge ASouthampton B1010020ME
CatholicColumbia A1010020ME
Central Florida AFlorida C1010020ME
Central Florida CCentral Florida B010010E
Chicago AIllinois B1010020ME
Chicago BNorthwestern B10101030MEH
Chicago ENorthwestern D10101030MEH
Cornell ARochester010010E
Cornell BCornell C010010E
Dartmouth AHarvard B1010020ME
DukeJames Madison B1010020ME
Edinburgh ACardiff1010020ME
Florida BFlorida A010010E
GeorgetownVassar010010E
Georgia Tech BGeorgia Tech D1010020ME
Georgia Tech CLouisville B1010020ME
Harvard ABowdoin B010010E
Illinois AChicago C1010020ME
Imperial BMontpellier1010020ME
Indiana BIndiana C010010E
Iowa StateCarleton College1010020ME
James Madison ANC State B010010E
John JayColumbia B010010E
Louisville AWashU B1010020ME
MITBowdoin A1010020ME
Maryland ANYU C1010020ME
Michigan APittsburgh1010020ME
Minnesota AWashington A1010020ME
Missouri AClaremont010010E
Murray State ATexas B1010020ME
NYU ANYU B1010020ME
North Carolina ALiberty B1010020ME
North Carolina CVCU1010020ME
Notre Dame AChicago D010010E
Notre Dame BNorthwestern C010010E
Ohio State AMichigan B1010020ME
Ohio State BMichigan C1010020ME
Ohio State CMichigan State1010020ME
Penn StateBinghamton B1010020ME
Purdue AIndiana A1010020ME
Purdue BIllinois C010010E
RITBinghamton A1010020ME
Rutgers AJohns Hopkins A010010E
Rutgers BMaryland C010010E
Stanford AStanford B010010E
SwarthmoreMaryland B1010020ME
Tennessee AAlabama B010010E
Texas A&M ATexas A010010E
UCLA AUCSD B1010020ME
UCLA BUC Santa Barbara010010E
UCSD AUC Irvine1010020ME
VirginiaNorth Carolina B1010020ME
Virginia Tech ASouth Carolina B1010020ME
Virginia Tech BLiberty A010010E
Wake ForestLiberty C1010020ME
Warwick ASouthampton A1010020ME
Warwick BManchester1010020ME
WashU ASewanee1010020ME
Washington BMissouri B1010020ME
William and MaryNC State A1010020ME
YaleDartmouth B1010020ME

Summary

TournamentEditionMatchHeardPPBE %M %H %
California (North)Main Site✓316.67100%67%0%
California (South)Main Site✓417.50100%75%0%
FloridaMain Site✓313.33100%33%0%
Great LakesMain Site✓420.00100%100%0%
Lower Mid-AtlanticMain Site✓917.78100%78%0%
MidwestMain Site✓917.78100%56%22%
NortheastMain Site✓618.33100%83%0%
OverflowMain Site✓417.50100%75%0%
South CentralMain Site✓215.00100%50%0%
SoutheastMain Site✓715.71100%57%0%
UKMain Site✓620.00100%100%0%
Upper Mid-AtlanticMain Site✓815.00100%50%0%
Upstate NYMain Site✓415.00100%50%0%