But that is not the case with water. Instead of contracting, it expands. The water molecule , consisting of 2 atoms of hydrogen and one of oxygen forms a Mickey Mouse head-like structure such that the ears are the hydrogen atoms and the head is represented by the oxygen atom. The oxygen atom side of the molecule is slightly negative while the hydrogen atoms side has a slight positive charge. This makes the water molecules drawn towards each other forming hydrogen bonds.
Upon freezing, the molecules set themselves in an arrangement that is very open in nature and contains more space than the water in the liquid state.
Hence, water is said to expand on freezing and becomes less dense. On the other hand, it contracts on thawing, much unlike most other liquids. What makes water so special? At normal atmospheric pressure, matter behaves in predictable ways as its temperature changes. Molecules fly apart into a gas when heated, condense into a flowing liquid when cooled, and shrink into a frozen solid when chilled still further.
The changes in state follow changes in energy - from high energy to barely jiggling. When liquid water boils at degrees, it expands into a gas steam and floats away.
But water also expands when it freezes. Chilling water does a slow shrink as its internal motion decreases. But at 39 degrees, a parcel of water reverses course, its volume slowly increasing as it cools further.
When someone likes another they will tell someone else they like them but the person they tell will maybe shout it out to there class in my case is it be cuz of jealousy or other reasons?
I would appreciate and answer to my question.. Who knows why people do what they do. Since oxygen forms 4 bonds with hydrogen during ice formation I have always pictured the reason for expansion as the return of the electron to the hydrogen atom.
The equal opposite pull on the electron puts it in the middle. Right where the hydrogen is hanging out. Giving hydrogen back its electron cloud triples the number of electron clouds compared to water and gas and the bonds become more covalent like rigid.
The structure then becomes the most logical arrangement and the neg neg interactions cause the expansion. Would you say that this is a correct statement "The hydrogen bonds of water expand during the freezing process, creating more volume and decreasing density of the ice. The hydrogen bonds do not expand; the way that the water molecules arrange themselves in three-dimensional space is a more open, less compact structure.
There is no such thing as cooling. There is removal of heat, or , energy. The energy must travel through a medium in order to get to whatever is pulling the energy out.
Since Hydrogen and Oxygen are the media, they get pulled and flow outward and apart. The bond between these molecules, due to their positive H and negative O charges, creates an opposing force to the force that is removing the energy. As the process progresses, and the water expands further, the force of the molecular bond and of whatever is taking the energy from the water, cancel out, creating the frozen water. AKA Ice. The molecules are suspended between two forces with little motion in either direction.
The outer molecules move slower than the innermost molecules. This is why you see lakes with liquid water covered by ice in the winter. Correct me if I'm wrong. This reminded me of the rubberband trick, stretch a rubberband almost to the breaking point for 10 seconds, let it contract back to it's normal state quickly, still holding onto the rubberband you can feel the rubberband absorbing the heat energy from your hand.
It "feels" like the rubberband is cold, but it's just the transfer of heat. The shrinking elastic band is "doing work" to re-compact and coil the stretch rubber polymer chains. Doing work consumes energy, so the average energy of the polymer chains - and hence the temperature of the rubber band falls i. So, pretty much when the particles or the solid substance gain energy, they get hot so the particles tend to expand causing the solid to expand?
Your explanations are great! Skip to main content. Earth Science. Articles Answers to Science Questions Why does water expand when it freezes? Why does water expand when it freezes? Part of the show Why does Water Expand when it Freezes? Then the freezing temperature is reached, and the substance solidifies, which causes it to contract some more because crystalline solids are usually tightly packed. Water is one of the few exceptions to this behavior.
When liquid water is cooled, it contracts like one would expect until a temperature of approximately 4 degrees Celsius is reached. This unusual behavior has its origin in the structure of the water molecule.
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