Question

The process in which gas is transformed into solid is called.
A) Sublimation.
B) Condensation.
C).Deposition.
D). Melting.

Answer 1

Hint: We know that if there is a change temperature or pressure of the system phase also gets changed. If the temperature or pressure increases the interaction between molecules also increases. Likewise, if the temperature or pressure decreases molecules move freely and the atoms settle into a more rigid structure.

Complete step by step answer:Given,
Now, we see the Sublimation process.
Sublimation is the process in which solids directly change to gases. Sublimation occurs if solids absorb enough energy to overcome the forces of attraction between them. Example: Dry ice is solid which undergo sublimation. Hence, Option (A) is incorrect.
Next, we discuss Condensation process.
The process in which a gas changes to liquid is known as condensation.
Example: Hot water from the shower gets evaporated and when it comes in contact with cooler surfaces it cools. The cooled water particles have no energy to overcome the forces of attraction between them so they form droplets of liquid water.
Therefore, option (B) is incorrect.
Next, we discuss the melting process.
Melting is the process in which solid changes to liquid. The temperature at which the solid changes to liquid is called melting point
Example:
If the ice cubes are taken out from the freezer and placed in a warm room, the ice would absorb energy from the warmer air around them. This absorbed energy helps them to overcome the force of attraction holding them together and it becomes liquid.
Now, we see the deposition process.
The thermodynamic process, in which gas transforms into solid, is called deposition.

$\therefore $The option C is correct.


Note:
We must know that the deposition process is the reverse process of sublimation. We can call it a sublimation reaction. Also we know that the sublimation is phase transition which changes from solid phase to gas phase directly.