Question

Rivers and lakes do not freeze easily. Why? ​

Answer 1

Answer:

Solution. Large rivers do not freeze "through out" because, Water, ice, and snow are good insulators and poor conductors of heat. The portions of a lake or river that are exposed to the cold winter air will freeze into ice and this ice insulates the water below from further rapid freezing.

Answer 2

Answer:

The density of water is approx. one gram per cubic centimeter. It is dependent on its temperature but the relation is not linear. When cooled from room temperature liquid water becomes dense but at 4 °C pure water reaches its maximum density. As it is cooled it expands to become less dense. So the layer of ice floats on water as insulating layer. The warm layer settles at the bottom in winters.

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