Multiple choice

A lake freezes due to cold temperature. It will first freeze

  1. at the bottom

  2. in the middle part

  3. at the top surface

  4. uniformly
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Water freezes from the top surface downward because of water's unique density anomaly - liquid water is densest at 4°C, while ice is less dense than liquid water. This means colder water rises to the surface, and ice floats. The surface reaches 0°C first and freezes, while deeper water remains liquid longer.

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