Strange behavior of the density of the water around the freezing point

In summary, the conversation discusses the strange behavior of water density around the freezing point and the factors that contribute to it. The main reason for water expanding at this point is due to the polar nature of its molecules, which causes them to line up and take up more space. This phenomenon only applies to fresh water and not seawater. The conversation also touches on the density curve of supercooled water and the role of hydrogen bonding in this behavior.
  • #1
bolbol2054
17
0
please is there a topic that discuss with illustration factor that causes Strange behavior of the density of the water around the freezing point
 
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  • #2
Can you be more specific?
Do you mean why it begins to expand?

That's fairly simple; water begins to expand because its poles are trying to line up so it can form a crystaline matrix.

Get ten people to crowd together in the centre of a room with their arms outstretched. They could probably crowd together pretty closely - outstretched arms overlapping and intertwined - if you herded them together.

Now, with their arms still outstretched, tell them to move around so they can hold hands with each other. They won't be able to grab each others' hands until they step back a pace or two. They'll take up more of the room.
 
  • #3
I presume you mean the fact that the maximum density is around +4 degrees centigrade?

This is due to the highly polar nature of the water molecule because of its shape.

Please note this is only applies to fresh water ie pure water. Water with dissolved material eg seawater does not exhibit this phenomenon.
 
  • #4
i meant with strange behavior that water contradicts the role of decreasing density due to increasing temperatur at a range from 0 c degree to 4 c degree
 
  • #5
Studiot said:
I presume you mean the fact that the maximum density is around +4 degrees centigrade?

This is due to the highly polar nature of the water molecule because of its shape.

yes sir that's exactly what i meant but i want to know with more diagramatic illustration the effect of molecule's shape on this behaviour i thought that such basic phenomena had a lot of discussion in previous threads
 
  • #6
Is your question, why is water less dense at 2C than at 4C even though it isn't ice?

Heck if I know. I'm not a chemist. But as an aspiring odds-maker, my money says that an increase in the time that hydrogen in one molecule temporarily bonds to oxygen in another dominates over the thermal agitation that would separate them.

Was that the question? If so, I wonder what the density curve of supercooled water looks like.
 
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What causes the density of water to behave strangely near its freezing point?

Water molecules are made up of two hydrogen atoms and one oxygen atom. When water is in its liquid form, these molecules are constantly moving and forming weak bonds with each other. However, as the temperature decreases, the molecules start to arrange themselves in a more orderly manner, resulting in a decrease in volume and an increase in density. This is because the molecules are able to form stronger bonds with each other, causing them to be packed more tightly together.

Why does water reach its maximum density at 4 degrees Celsius?

At 4 degrees Celsius, the hydrogen bonds between water molecules are at their strongest. This allows for a maximum number of molecules to be packed into a given volume, resulting in the highest density. As the temperature decreases further, the molecules start to arrange themselves in a more organized crystalline structure, causing the density to decrease.

Does the density of water change uniformly as it approaches its freezing point?

No, the density of water near its freezing point does not change uniformly. As the temperature decreases, the density of water starts to decrease until it reaches its maximum density at 4 degrees Celsius. After that, as the temperature continues to decrease, the density starts to increase again. This is due to the formation of ice crystals, which are less dense than liquid water and therefore cause a decrease in overall density.

What are the implications of the strange behavior of water's density near its freezing point?

The unusual behavior of water's density near its freezing point has several important implications. Firstly, it allows for bodies of water to freeze from the surface downwards, providing insulation for aquatic life during the winter. It also means that ice can float on top of liquid water, preventing bodies of water from freezing completely and allowing for life to survive underneath. Additionally, this behavior also plays a crucial role in regulating Earth's climate and weather patterns.

Is the strange behavior of water's density near its freezing point unique to water?

No, the strange behavior of water's density near its freezing point is not unique to water. Other substances, such as silicon, bismuth, and gallium, also exhibit similar behavior. This is because they all have atoms that form strong bonds with each other, resulting in a decrease in density as they approach their freezing points.

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