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When rivers get frozen to form ice in winter season, how does the layer below ice remains liquid? View All
Water gets frozen to form ice in winter. But a layer below ice gets to remain in the same liquid state. The phenomenon behind this science is.....

7 years ago - 1 month left to answer. - 2 responses - Report Abuse
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Anomalous expansion of water: beyond 4 degrees Celsius, water "contracts", its density increases hence it becomes heavier than ice which "expands" and decreases in density. Below -4 degrees the reverse is true. However, as to why this occurs is unknown! Why?

7 years ago


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Actually the reason for this expansion is well known. It has to do with the polar nature of the water molecule. When it is in the liquid state the movement of the molecules allow them to fill in the spaces in the crotch of between the two hydrogen atoms [1]. When water freezes it becomes a very well ordered tetrahedral or hexagonal lattice which expands by about 9% and is lighter.

There are a number of other substances which exhibit this behavior (e.g. silica,

Niel Leon

7 years ago

Source: [1]

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