Melting

“Colorful Colorado”. That name seems quite appropriate with the lush green landscapes in the summer, all the wildflowers and rolling plains, the Rockies reaching towards the heavens, and in the winter the vast blanket of pure white snow signaling it’s time for snowboarding (or skiing if you’re one of those). With the first fall of snow everyone on campus seems to be in a jolly good mood making snowmen and throwing snowballs or whatever it is you decide to do in the snow. Until about three days later after you’ve slipped and fallen on your rear or had an entire tree unload it’s weight in snow on top of you. By that point you’re cursing the heavens and skipping class because you refuse to walk a mile to campus and end up with squishy, wet socks again. That’s when the sudden shift of Colorado weather causing the snow to melt away becomes a miracle. Oh, the sweet warmth of the sun saving you from that pure, white hell. Is it the warmth of the sun that causes the snow to melt? Partially. That’s called sensible heat: heat that changes temperature, such as fire. But the more interesting part of melting process is this little known thing called latent heat.

Allow me to explain:

For starters, I’m sure you are aware that melting is when water goes from a solid ice or snow form to a liquid. The sensible heat changes the temperature of the snow until it reaches it’s melting point. This is the point where latent heat kicks in and a phase change occurs. You see, once the melting point is reached the introduction of heat cannot be observed any longer as a temperature change, as the temperature remains constant during the entire process of the phase change. So sensible heat doesn’t matter at this point. What latent heat is doing to cause the snow to melt into water is taking energy from the environment and transferring it to the water, which weakens the individual hydrogen bonds between the water molecules, allowing the molecules to end up in a liquid state. Because the snow is taking energy from the environment to melt, the environment around is subsequently cooled down. Nifty.

SMART PEOPLE PARTY FACTOID TIME: The amount of energy it takes during the phase change from solid to liquid 80 cal/g.