How to stop melting of the ice
- salt - sodium chloride,
- ice cubes,
Freeze water into ice in the molds. Then place ice cube in plate. When the ice starts to melt so as to sprinkle salt on 33g attributed to salt 100 g of ice.
When the snow or ice sprinkle with salt, obtain a liquid solution having a temperature below 0 ° C, depending on the concentration of the solution. The lowest temperature of -21.5 ° C when the ratio of ice and salt is 3:1.
Salt added to ice, dissolving in the solution concentration increases and lowers the temperature increasing (to -21.5 ° C). Such a mixture is called Freezing (Spine). Both of the above-described phenomenon can be explained on the basis of molecular structure. Salt diffuses into the ice and affect the crystal structure. There are defects in the crystal lattice, and therefore, it is easier to disrupt the binding of the network. What is needed is to lower energy. As a measure of the air temperature or ice is the average kinetic energy of the particles making up, this means that such a network no longer be stable at the lower temperature (at lower energy).