Does an ice cube melt faster in air or water or salt?

Answer 1

Melting IceIce melts when heat is transferred away from it to its surroundings. Water is denser than air, so heat is conducted away from the ice faster in water than in air, all other things being equal. (Note: it's actually not its density that matters but rather its heat capacity. Things with high heat capacities are better at removing heat from other things because their temperature will increase less for the same amount of heat removed. Often things with higher density have higher heat capacity, but not always. Liquid always have higher heat capacities than gases do though).

But if you submerged the ice in ice-water -- water at or near zero degrees Celsius (or 32 degrees F) -- then the ice may melt faster in the air, especially if the air is warm and moving. How fast something melts has to do with both the nature of the surrounding medium (gas vs. liquid for instance), but also its temperature.

By the way, ice water will also chill things faster than very cold air. If you submerge a test tube of room-temperature water in an ice bath, it will coll down much more rapidly than if you had placed the test tube in the freezer, even though the freezer is colder than the ice bath. Again, this has to do with the higher heat capacity of water than air.

(That makes for an excellent, yet simple, experiment for a science fair. It's cool -- pun intended -- because it has an unexpected result.)

See the Web Links for more information about heat capacity.

[Note: I'm no physicist, but what you have here seems intuitively wrong. "Ice melts when heat is transferred AWAY from it TO its surroundings" [emphasis added]. Shouldn't the energy of the ice be increased rather than decreased (i.e. heat is transfered TO the ice FROM its surroundings)?]

Answer 2

=Because water is a fluid.==Air as a gas has a much lower density of particles that water, and salt as a solid has particles that are constricted in a solid crystal and cannot move around as freely as the molecules in water.==Thus, the molecules of fluid water can make contact with the ice cube surface much more often and transfer much more heat (thermal energy) per time to the ice cube than the air or salt particles can, and thus cause the ice cube to melt considerably faster.=

Answer 3

In hot water hopefully you know that the atom's move faster than those in cold water. So the movement of the atom's in the hotter water create more friction than those in the cold water. The more friction the more heat equals the faster the ice cube melts.

Answer 4

The transfer of energy from the hot water to the ice is faster than that from the warm water to the ice due to the higher temperature of the water. (The rate of energy transfer between two bodies is proportional to the difference between the temperatures of the two bodies)

Answer 5

An ice cube will melt faster in water because water is a better conductor of heat than air. Adding salt to water can actually slow down the melting process due to the effects of freezing point depression, which lowers the melting point of the ice.

Answer 6

water Ice takes about 1- 2 hours to melt with salt and about 5 hours with air