What is freezing weather?

Answer 1

Freezing point is defined as the temperature at which the vapour pressure of the liquid is equal to the vapour pressure of the solid.

Vapour pressure arises due to the vapourisation of liquid from the surface. Vapour formation is proportional to temperature. As temperature increases, the liquid vapourises faster and hence vapour pressure (VP) increases. And as a fact, VP of solids is lower than liquids due to stronger London forces in solids.

From this, we can conclude that VP of:

solid at lower temperatures < solid at freezing point = liquid at freezing point < liquid at higher temperatures

Let's consider a liquid whose temperature and VP is above that of the freezing point. To freeze it, its VP must be decreased so that it becomes equal to that of the solid. VP is decreased by reducing temperature.

However, if a non-volatile solute is added to the solvent, the VP decreases at a given temperature. Now, it will become equal to that of solid solvent at a lower temperature (Raoult's law). To understand how the equality is achieved at low temperatures, follow the freezing point depression graph.

Y-AXIS

|____________________________C.

|_________________________.__

|_____________________.________.D

|__________________.________.

|_____________B_.________.

|____________._|_____.__

|__________.___|_.

|________.__.__|_

|______A.______|

|______._|_____|

|____E.__|_____|

|________|_____|

|________|_____|

_------------------------------------------X-AXIS

-------------T1------ T2

EAB- a slightly curved line for solid solvent

BC- a slightly curved line for liquid solvent

AD- a slightly curved line for solution

X AXIS- Temperature in K

Y AXIS- Vapour Pressure

A and B are the freezing points of the respective substances

Inference from the graph:

At T2, the vapour pressure of solution is lower than that of pure solvent (implied by 'However, if a non-volatile solute is added to the solvent, the VP decreases at a given temperature').

The solution curve meets the solid curve at a freezing temperature lower than that of the pure solvent (implied by 'Now, it will become equal to that of solid solvent at a lower temperature (Raoult's law)').

Thus, a solvent's freezing point (temperature at which a solvent freezes) can be reduced/depressed by turning it into a solution.

For example, salt added to water will prevent it from freezing at 0 degree celsius.

Answer 2

Freezing weather is when the outside temperatures are so cold that ice is formed, when man/woman needs to take out all their Thermal clothes in order to keep warm, and when ice is formed on your eyebrows and hair etc.

Answer 3

It means that the temperature has gone below 32 degrees Fahrenheit or 0 degrees celsius.

Answer 4

it is a figure of speech if your really cold

Answer 5

31 degrees