Order from us for quality, customized work in due time of your choice.
The state change of water and melting of ice are among the foremost dramatic transitions of phase occurring nature. Melting ice accounts could be an event that one observes in his/her everyday lives during which the liquid layer created on ice chunks promote the transfer of mass and charge throughout collisions between them; frost heaving powerful enough to carry boulders from the bottom; and, of course, slippery surfaces.
Introduction
Day to day life expertise suggests why ice surfaces ought to be slippery: Water spilled on a room floor or rain on asphalt or concrete will produce a similar sorts of hazards for walkers and drivers that ice will. Presumably, the liquids are mobile so, it will makes the surface slippery, whereas solid surfaces are comparatively rigid. Asking why ice is slippery is approximately same as asking a liquid or liquid-like layer will occur on the ice surface within the initial stage. A slender film of fluid covers the outside of ice—even at temperatures well underneath solidifying. Dismissed for almost a century, the elements of ice surfaces has now developed into a functioning research point.
Pressure Melting
For quite a while, the normal observation was that skaters slide more effectively on ice than on different solids. Water is denser than ice and possesses about 10% less volume per mole. So as indicated by Le Chatelier’s rule, an expansion in pressure brings about dissolving the ice and diminishes the example’s volume. That is, if dissolving had happened independent from anyone else, it would have brought about a lessening in pressure.
Referring to work of Kelvin brothers, who gave linear relationship between freezing point and pressure. This hypothesis was tested on skiing and ice skating. This experiment carried out practically on skater’s blade and they had found that this theory valid only for freezing temperature near -3°C. Some winter sports like Ice skating and skiing are even played at lower temperature like – 30°C and we can see slipping. For this theory to be right for temperature like -30°C the pressure must be very high such a high pressure cannot be created by a person. Also such a high pressure squeeze the water film which eventually resist slippage.
Frictional heating
Another hypothesis is suggest that film of water is created by localized heat produced due to the friction. This friction varies according to speed and static kinetic friction co-efficient. This explain why iron skies and skates resist motion in compare to wood.
Yet a question arises that why ice is slippery even if we stand still? Phase diagram of H2O. Ice exhibits a rich variety of crystalline and glassy structures in at least 11 distinct phases (7 are shown here) at different pressures and temperatures. The ice–water phase transition is simpler. The meltingtemperature increases steadily with pressure ex- cept at low pressures, where the familiar hexago- nal ice-Ih structure is less dense as a solid than a liquid. (Diagram courtesy of Steven I. Dutch, Uni- versity of Wisconsin at Green Bay.)
Theory of Loose molecules
Latest studies suggest that slipping is due to loose molecule layer of water over ice and not a film of water. It can be imagine as rolling over room full of marbles. This layer is so free that it can be imagine as 2-D gas molecule rather than 3-D water molecule. But for temperature -40°C ice act as sand paper. And due to less energy within it doesn’t create or break bond hence ice is not slippery at -40°C or below.
Conclusion
The about document state that slippage of ice is depends on various factors like Atmospheric temperature and pressure, friction and molecular structure of water. Each hypothesis which is mentioned has its own limitations. But combination of these theories explains the reason why ice is slippery.
References
- Contributor, M. (2019). Why Is Ice Slippery?. [online] livescience.com. Available at: https://www.livescience.com/62621-why-is-ice-slippery.html [Accessed 10 Nov. 2019].
- J. Thomson, Proc. R. Soc. London 10, 151 (1859-1860); https://doi.org/10.1098/rspl.1859.0032
- Lptms.u-psud.fr. (2019). [online] Available at: http://lptms.u-psud.fr/membres/trizac/Ens/L3FIP/Ice.pdf [Accessed 10 Nov. 2019].
Order from us for quality, customized work in due time of your choice.