Icy roads
Classical Mechanics
Level
2
A freezing rain deposited a layer of ice on the surface of a road. We put salt on it and the ice melts while the melted water dissolves the salt. This salt solution is ... pick you option.
warmer than the original ice.
colder than the original ice.
the same temperature as the original ice.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
When ice and salt are mixed and the ice melts the heat that is necessary for the melting comes mostly from the salt solution that is produced at the same time. Therefore the salt solution is colder and eventually the remaining ice will be also colder.
This has been well known for a long time and it had been used in old-style ice cream making machines, before the invention of the refrigerator.