A reclusive scientist was found dead in his locked laboratory. On the whiteboard, he had written a final sequence: 'H2O, NaCl, C12H22O11, KCN.' The local police assumed it was a chemistry puzzle. Detective Vance immediately identified the lethal substance that killed him from the list. Which one was it?
KCN
KCN is Potassium Cyanide, a notoriously fast-acting and lethal poison, whereas the others are water, salt, and table sugar.
About this riddle
Detective riddles are tiny mysteries. Look for the detail in the story that does not fit; it is usually the clue that solves the case.
Difficulty: Easy. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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