What is depression of freezing points?
The depression of freezing points is when the addition of a solut is a normal freezing point of liquid. Each liquid has a normal freezing point; For example, pure water freezes at 32 degrees Fahrenheit (F) (zero degrees Celsius or C). Salt in seawater brings seawater to a lower freezing point than in clean water; However, seawater can still freeze, the temperatures at which they do so are lower than the water from the pure water source. This is what allows ice cream in the freezers of ice cream when the metal canister in the middle is surrounded by rock salted ice. The melting of ice salt allows a mixture of ice cream to lose heat into the surrounding icy water, thus freeing the ice cream.
Scientists have noted that the amount of solut added to the liquid is directly proportional to the depression of the freezing point that is successful. The molecules in the solution freeze not only at a lower temperature, but the cooling at the freezing point takes place at a milder rate than in pure liquids.The basis for the use of salt or sand on ice roads in winter is the ability to freeze freezing. Molecules of salt or sand, spread on roads, mix with ice and cause melting, which is particularly useful for black ice, which is so dangerous to vehicles. The heavy spread of salt can reduce the depression of freezing point up to mere zero stages F (-18 ° C).
When salt extends over ice, there is a chemical exchange between molecules. The surface molecules of ice begin to escape into the melting water and the surface molecules of the water are captured in the surface molecules of water. This shift between the molecules is caused by fluctuations at temperatures of anyone who gradually heats and melts the remaining ice because the molecules escaped and accelerated. The added mixture introduces molecules of foreign substances that are not easy to kill into solid and accelerated. For this reason, any foreign substance - alcohol, sugar or salt - the same effect would be introduced, although salt is widely available and cheaper to use.
Depression BodeM frost is the intention of adding antifreeze to radiators in car vehicles. Adding ethylene glycol, the main antifreeze, creates a solution of water. People in a different cold climate can use different percentage of antifreeze to water to achieve different depression, but if there is more antifreeze in the water than the opposite, the opposite effect occurs and freezing points rather than depression. It is recommended to read the parties of the antifreeze to determine the best percentage to be used, especially the climate.