Bonus
Tetramethylsilane is used as an internal standard for calibration in this technique’s “proton” and “carbon-13” variants. For 10 points each:
[10m] Name this spectroscopic technique in which signals are normalized to chemical shift values. This technique investigates the structure of molecules by applying a strong magnetic field before perturbing them.
ANSWER: NMR spectroscopy [or nuclear magnetic resonance spectroscopy; accept proton NMR; accept carbon-13 NMR]
[10h] The sample holders in NMR spectrometers perform this action to average out diffusional motion. In one form of NMR, this action is performed at a “magic angle” of 54.7 degrees to improve resolution.
ANSWER: spinning [accept magic angle spinning or magic angle turning; accept word forms like spun or turned; accept synonyms like rotating or word forms like rotation]
[10e] Magic angle spinning is used in a variant of NMR that analyzes samples in this state of matter. Substances in this state of matter have closely packed atoms and have a definite shape and volume.
ANSWER: solid [accept solid-state NMR or solid-state nuclear magnetic resonance]
<Edinburgh C, Chemistry>
| Editions | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|
| 2 | 106 | 17.08 | 99% | 61% | 10% |
Conversion
| Team | Opponent | Part 1 | Part 2 | Part 3 | Total | Parts |
|---|---|---|---|---|---|---|
| Macalester | Iowa State | 0 | 0 | 10 | 10 | E |
| St. Thomas | Michigan Tech | 10 | 10 | 10 | 30 | MHE |
| Wisconsin A | Minnesota | 10 | 0 | 10 | 20 | ME |
| Wisconsin B | Wisconsin C | 0 | 0 | 10 | 10 | E |
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| Northern California | US | Y | 4 | 22.50 | 100% | 100% | 25% |
| Southern California | US | Y | 7 | 21.43 | 100% | 100% | 14% |
| Eastern Canada (1) | US | Y | 4 | 17.50 | 100% | 75% | 0% |
| Eastern Canada (2) | US | Y | 9 | 15.56 | 100% | 44% | 11% |
| Florida | US | Y | 4 | 10.00 | 100% | 0% | 0% |
| Great Lakes | US | Y | 10 | 20.00 | 100% | 70% | 30% |
| Lower Mid-Atlantic | US | Y | 9 | 15.56 | 100% | 56% | 0% |
| Upper Mid-Atlantic | US | Y | 9 | 18.89 | 100% | 67% | 22% |
| Midwest | US | Y | 9 | 17.78 | 100% | 78% | 0% |
| North | US | Y | 4 | 17.50 | 100% | 50% | 25% |
| Northeast | US | Y | 12 | 13.33 | 100% | 33% | 0% |
| Pacific | US | Y | 8 | 16.25 | 100% | 50% | 13% |
| Southeast | US | Y | 12 | 17.50 | 100% | 67% | 8% |
| Upstate NY | US | Y | 5 | 16.00 | 80% | 80% | 0% |