Sports Science Friday: Ice, Ice, Baby

Winter sports season is upon us, MFans. As is Michigan's winter weather. Wednesday morning I had to pour hot water on my car to unfreeze it just enough to crank the door open. You see, Tuesday's rain jumped physical states, encasing my car, and my mood in a block of ice........... This, of course, took me right down the free-association freeway back to previous 8 AMs in my life... when I would step off of the Bursley Bus in the freezin' f'n cold to go to freshman chem (greeted ever so sickeningly by that oniony, grease-laden smell of breakfast potatoes wafting out of the League, and hanging mysteriously in the cold dark air). This, dear reader, is how my mind works. Just ask Andy....

And how we get to this week's subject for Sports Science Friday: ICE.

Return with me now to basic chemistry and the structure of ice. As you recall by yonder phase diagram of H2O on the left, ice is a curious beast. At zero degrees celsius liquid water becomes solid ice. Even more mind boggling is that the solid form of H2O is less dense than the liquid form. That's why ice cubes float.....

Ice as we know it is comprised of a gigtybillion water molecules arranged in an hexagonal array. Why ice is slippery is a topic of much debate.

When it comes to hockey and skating, there is a whole science to sharpening one's blades and producing an edge. Once upon a time people thought that the thin sharp blades created a tremendous amount of force over a small area thereby 'melting' the underlying ice with pressure. It was thought that this thin layer of newly melted water was what one skated upon. But that makes no real sense since you can definitely slip on ice with flat bottomed shoes.... So then someone else said, no no no. It's not pressure that melts the ice, it's the heat from the friction caused by contact with the ice.....that gives you the water to slide/skate on. Whatever dude!

A professor of surface chemistry at UC Berkeley, named Gabor A. Somorjai realized that what really is happening is that the surface water molecules are getting all jiggy-wid-it and vibrate in place. This means that they aren't exactly solid at all, like the molecules buried within the center of the sheet, but rather they remain as a liquid since only one side is snuggled up against other molecules. This is why, as Faraday pointed out in the 1800s that if you put two ice cubes together they stick and become solid. The 'outside' liquidy vibrating water gets pressed up against other molecules thereby allowing transition into a glorious solid phase.....

And why, dear reader one should never ever never stick your tonque on cold metal.......

More on those hockey skates next week!!!