Question

What do you understand by the term that ${K_f}$ for water is $1.86Kkgmo{l^{ - 1}}$ ?

Answer 1

Freezing point depression refers to the lowering of the freezing point of solvents upon the addition of solutes. It’s a colligative property of solutions that's proportional to the molality of the solute that has been added.

Complete answer:
When we say that the ${K_f}$ of water is $1.86 Kkgmo{l^{ - 1}}$ it means that ,when $1$ mole of non-volatile solute is dissolved in $1kg$ of water, the freezing point of water is dropped by $1.86Kkgmo{l^{ - 1}}$ .
The following are some of the most common applications of freezing point depression.
Sodium chloride is poured over the roadways in cold places with temperatures ranging from ${0^ \circ }C$ to $- {15^ \circ }C$ to reduce the freezing point of water and prevent the formation of ice.
Calcium chloride is used instead of $NaCl$ to melt the ice on the roads when the temperature is below ${18^ \circ }C$ . This is due to the fact that $CaC{l_2}$ dissociates into three ions, lowering the freezing point of water.
Ethylene glycol and water are commonly utilised in radiator fluids in numerous autos. This keeps the radiator from freezing in the winter.
The freezing point depression formula can be used to calculate the molar mass of a given solute.
This formula can also be used to determine the degree to which a solute dissociates in a solvent.

Note :
The freezing point of a liquid is the temperature at which it transforms into a solid. The melting point of a solid should, in theory, be the same as the freezing point of a liquid. Small changes between these quantities can be observed during the action.