Solved cryptogram
The periodic table is arranged by proton count, not by weight, and that fixed several errors.
Chemistry Facts, sourced to Royal Society of Chemistry.
Solve it yourself
This fact is a cryptogram here: 75 letters over 21 different ones, graded medium.
Or go to the puzzle’s own page first.
What it means
Mendeleev sorted by atomic weight and had to swap a few pairs to keep the chemical families lining up, with no justification beyond the fact that it worked. Moseley showed in 1913 that the X-rays an element gives off track a whole number, and that number is the charge on the nucleus. Sorting by it put the awkward pairs in the right order for a reason, and it also said exactly how many gaps were left to fill.
The claim comes from Royal Society of Chemistry.
- SourceRoyal Society of Chemistry
- CollectionChemistry Facts
- Difficultymedium
- Length75 letters, 21 of them different
Nearby in the collection
The facts either side of this one.
- U.S. Department of Energymedium, 70 letters
- CIAAW, IUPACmedium, 71 letters
- Royal Society of Chemistryhard, 77 letters
- Royal Society of Chemistryeasy, 76 letters
About as hard as this one
Scored closest to it by the model behind our guide to solving cryptograms.
- Royal Society of Chemistrymedium, 71 letters
- Royal Society of Chemistrymedium, 73 letters
- Royal Society of Chemistrymedium, 77 letters
- NASAhard, 68 letters