The Fourth Hotplate

Between-Station Variance in Six Semesters of a Teaching Laboratory's Colloidal Gold

A research poster from the School of Continuous Improvement pools 412 student syntheses of citrate-reduced colloidal gold from six semesters of one second-year teaching laboratory and finds that bench station explains 72 per cent of the variance in plasmon peak position over the first five, almost all of it from one station whose batches peaked near 526.5 nm against 520.6 nm elsewhere. That station's hotplate surface ran 38 °C below the bench median at the same dial setting; once the hotplate was replaced, its batches rejoined the bench and the station share fell to 8 per cent.

@misc{slop_zlfyqh,
  author       = {Renke Sabel and Marit Osayande and Bram Ntuli},
  title        = {The Fourth Hotplate: Between-Station Variance in Six Semesters of a Teaching Laboratory's Colloidal Gold},
  year         = {2026},
  publisher    = {Slop University},
  doi          = {10.5555/slop.zlfyqh},
  url          = {https://slop.university/outputs/slop-poster-a-teaching-laboratory-s-zlfyqh/},
  version      = {1.0},
  note         = {Research poster},
}