Question

Why does the bottom of a lake not freeze in severe winter even when the surface is all frozen ?

• A. The water has large specific heat
• B. The conductivity of ice is slow
• C. The water has large latent heat of fusion
• D. The temperature of the earth at the bottom of the lake is high

Answer 1

Answer:

B. The conductivity of ice is slow

Conductivity of ice is low. The bottom of a lake do not freeze in severe winter. The reason is that ice is a poor conductor of heat hence once the surface is frozen no further heat is liberated or absorbed by water beneath ice. Therefore water below ice never freezes.