Chiral Crystallization of Ethylenediamine Sulfate
Bibliographic record
Abstract
Optimized conditions for the chiral crystallization of ethylenediamine sulfate, which can serve as an ideal undergraduate experiment, are described. Large, flat, colorless crystals of ethylenediamine sulfate are obtained in an undisturbed evaporation dish within a period of approximately five to seven days. The crystals are ideal for polarimetry studies and observation using Polaroid sheets. Students become familiar with polarizing filters and how they can be used to distinguish between dextrorotatory and levorotatory crystals. Of 100 randomly sampled crystals, 47 crystals showed a (+)-rotation, while 53 crystals showed a (-)-rotation. The absolute value of the average optical rotation of the 100 crystals was found to be 158/mm ± 2 for the D line of sodium. The relative direction of rotation of polarized light was also determined by simply observing the change in optical rotatory dispersion of the crystals placed between two Polaroid sheets as one of the sheets was rotated clockwise or counter clockwise.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".