Why do mirrors fog up in bathrooms?
Show answer & explanation
Answer: Steam condenses on cold glass
Steam condenses on cold glass ✓ — Correct! Hot shower steam hits the cooler mirror surface. Water vapor loses energy and condenses into tiny droplets. These droplets scatter light, making the mirror look foggy. Warming the mirror prevents this!
Soap residue attracts water — Wrong. Clean mirrors fog just as easily. The fog is water condensation from temperature difference, not soap attraction.
Hot air pushes water out — Wrong. Hot air holds more moisture, not less. When it contacts cool glass, moisture condenses out as fog.