I assume that the reason water freezes is because as you decrease the temperature, the kinetic energy of the water molecules decreases and the dipole bonding potential eventually over comes the escape velocity of the molecules and they form a crystal structure. What would happen if you attempted to freeze water in the presence of a very powerful electric field? Will the water molecules align to the field and make it harder to form a solid or easier to form a solid?
Answer
An electric field is not experimentally known to change the equilibrium freezing point of water of 0 C. However, water can be supercooled to -40 C, in the absence of nucleation sites. Electric fields affect the freezing of (unstable) supercooled water.
See this 2010 article in the journal "Science": http://www.sciencemag.org/content/327/5966/672
and "Electrofreezing of Supercooled Water" http://link.springer.com/article/10.1007%2FBF00875907
Although not demonstrated experimentally, there are computational models of water which predict that above $10^9 V/m$ an electric field would orient the dipoles of the water molecules and change the equilibrium freezing point of water.
No comments:
Post a Comment