Inspector Vance found the victim slumped over a desk with a frozen carbon dioxide cube melting nearby. The note read: 'Icy secrets fade in the warmth.' Vance immediately arrested the business partner. How did he know it was murder and not a natural event?
A melting carbon dioxide cube leaves no liquid water behind.
Dry ice sublimates directly from a solid to a gas. If there was a puddle, it wasn't carbon dioxide; if there was no residue, the killer staged it using dry ice which would leave the room eventually, but a puddle of water at a warm desk proves someone brought a fake clue or faked a natural melt.
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: Medium. More like this: Detective riddles with answers or try Truth & Lie Island for a different kind of puzzle.
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