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qid 4607 · chemistry

Question: The equilibrium populations of the 1H energy levels of a molecule are nα = nαeq and nβ = nβeq. What are the populations after a 5.0 μs pulse when B1 = 4.697 mT?

  1. nα = nβeq/2 and nβ = 2nαeq
  2. nα = nαeq + 2nβeq and nβ = nβeq + 2nαeq
  3. nα = 3nαeq and nβ = nβeq/2
  4. nα = nαeq/3 and nβ = 3nβeq
  5. nα = nαeq + nβeq and nβ = nαeq + nβeq
  6. nα = nαeq and nβ = nβeq
  7. nα = nβeq and nβ = nαeq
  8. nα = 2nαeq and nβ = 2nβeq
  9. nα = ½(nαeq + nβeq) and nβ = ½(nαeq + nβeq)
  10. nα = nαeq - nβeq and nβ = nβeq - nαeq

Our answer: G. nα = nβeq and nβ = nαeq Source quote machine-checked (exact quote)

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How it was answered

Multi-step solver (maze), replayed by code

card: maze · card sha256 04c598432e6d3078…

Current source

University of Oxford Department of Chemistry NMR, "Measuring relaxation times: Inversion recovery for T1" (Amin & Claridge, 2019)

https://nmr.chem.ox.ac.uk/files/measuringrelaxationtimespdf

“In the inversion recovery experiment, the nuclei are first allowed to relax fully to their equilibrium states along the z-axis. A 180-degree pulse is then applied, which inverts the signals.”

Source quote machine-checked (exact quote)

retrieved 2026-09-17T23:56:34.908Z

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addendum maze_qid4607_KEY_INFORMED_b4_maze_input_ADDENDUM_source_rs20260917T235634Z · sha256 8c69c65028487daa… · replaces the version below, addendum sha256 ad9aa09d5e7b6af9…

Earlier version (superseded)

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addendum maze_qid4607_KEY_INFORMED_b4_maze_input_ADDENDUM_source · sha256 ad9aa09d5e7b6af9…

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