You can’t see me, but I can make you feel tired and sluggish. What am I?

Category: Science · Difficulty: hard

Hint: I accumulate in closed spaces and can affect your alertness.

Answer

High carbon dioxide levels

Explanation

High levels of carbon dioxide can lead to feelings of fatigue and decreased cognitive function.

This is a hard science riddle — a tricky one that takes a little thought. The answer is High carbon dioxide levels.

More Science riddles

All Science riddles · Riddles with answers · Home