❓ why
Why Does Ice Float?
ChemistryPhysics
Quick Answer
Water expands when it freezes because hydrogen bonds lock molecules into an open crystalline lattice less dense than liquid water.
The Full Story
Most substances become denser as they solidify, but water is an exception. Below 4 °C, hydrogen bonds between water molecules begin to push them into a hexagonal crystal structure that spaces them farther apart than in the liquid state. By the time water reaches 0 °C and freezes, ice is about 9% less dense than liquid water, so it floats. This anomaly is critical for aquatic life: a floating ice layer insulates the water below, keeping it liquid and allowing fish and other organisms to survive winter.
Key Facts
1.Ice has a density of about 917 kg/m³, while liquid water at 4 °C is 1,000 kg/m³.
2.About 10% of an iceberg sits above the waterline due to the density difference.
3.If ice sank, lakes and oceans would freeze from the bottom up, making aquatic life far more difficult.
YouTube Angle
Suggested video title for this topic:
"The Weird Reason Ice Floats — And Why Life Depends on It"