What is KF formula?
Potassium fluoride is the chemical compound with the formula KF. After hydrogen fluoride, KF is the primary source of the fluoride ion for applications in manufacturing and in chemistry.
What factors affect freezing point depression?
The freezing point depression constant changes depending on the solvent, and the van ‘t Hoff factor accounts for the number of particles that a dissolving solute creates in solution.
What is the equation for freezing point depression?
The freezing point depression ∆T = KF·m where KF is the molal freezing point depression constant and m is the molality of the solute. Rearrangement gives: mol solute = (m) x (kg solvent) where kg of solvent is the mass of the solvent (lauric acid) in the mixture.
Which will freeze at the lowest temperature?
Which will freeze at the lowest temperature? Ocean water has the highest concentration of solute, so it will have the greatest freezing point depression, and therefore freeze at the lowest temperature of the three.
How do you find the lowest freezing point?
To compare freezing points, we need to know the total concentration of all particles when the solute has been dissolved. Remember, the greater the concentration of particles, the lower the freezing point will be.
Which has highest freezing point?
glucose solution
Which has the greatest freezing point depression?
sodium fluoride
Which element is the last to freeze?
Helium happens to be the only element that can’t be solidified or frozen at normal atmospheric pressure. Only once you apply a pressure of 25 atmospheres at Helium’s freezing point of −458 °F can you solidify it.
Does chilled mean frozen?
Chilling is before freezing, like frosting and still can be pliable. And freezing is frozen which may be rock hard. Refers to food that is thoroughly cooled in a refrigerator compartment, but is not frozen. Proper chilling of food is usually accomplished within a temperature range of 33°F to 42°F.
What Does lowest freezing point mean?
A solution will have a lower freezing point than a pure solvent. The freezing point is the temperature at which the liquid changes to a solid. This is true for any solute added to a solvent; the freezing point of the solution will be lower than the freezing point of the pure solvent (without the solute).
What is the difference between melting point and freezing point?
Melting poing is the temperature at which a solid changes to liquid under atmospheric pressure. Freezing point is the temperature at which liquid changes to solid under atmospheric pressure.
What is the difference between freezing and chilling?
In the food industry, freezing usually refers to deep freezing, or lowering the temperature of product below -18°C. In contrast, chilling refers to the rapid cooling of a food product from its manufacturing temperature down to refrigerated or cold temperatures, usually from 2 to 4°C.
What is the difference between freezing and chilling injury?
What are the differences between freezing injury and chilling injury? Both are low temperature injuries, but for freeze damage to occur, the product must be below its freezing point. Chilling injury occurs at a range of temperatures that are low but nonfreezing for that product.
What is the difference between freezing and deep freezing?
With freezing, the temperature of the food is decreased slowly, usually up to 24 hours. Deep freezing refers to a process where the food is exposed to a temperature from -30 °C to -50 °C so that the core of the product reaches -18 °C within an hour. Deep freezing is a method typically used in industrial settings.
How does deep freezing work?
Deep-freezing is an industrial technique which involves cooling rapidly and brutally (a few minutes to an hour) food by exposing them intensely to temperatures from -30 ° C to -50 ° C, until the product core temperature reaches -18 ° C. With this process, the water contained in the cells is finely crystallized.