Why does ice form on windows in winter?
Show answer & explanation
Answer: Indoor moisture on cold glass
Indoor moisture on cold glass ✓ — Correct! Indoor air contains water vapor from breathing, cooking, and other activities. When this warm, moist air touches a very cold window (below 0°C), the vapor deposits directly as ice crystals, skipping the liquid phase - a process called deposition. The beautiful frost patterns form because ice grows along scratches and imperfections in the glass!
Cold air contains ice crystals — Wrong. Cold air can hold very little moisture. The ice on windows comes from indoor water vapor that freezes when it contacts the cold glass surface.
Glass attracts frozen particles — Wrong. Glass doesn't attract ice particles. Ice forms when water vapor in warm indoor air deposits directly onto the cold window surface, creating frost crystals.
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