Question

i) What is the physical state of the substance at the points A and C?
ii) What is the melting point and boiling point of the substance?
iii) Which portions of the graph indicate the change of state?
iv) What is the term used to describe the phase change from gas to liquid?
a) Freezing b) Evaporation c) Condensation d) None of these

v) The substance is not water. How can you judge from the graph?​

Answer 1

I hope it will be help you

Phase Transition: Liquid to Gas

Vaporization of a sample of liquid is a phase transition from the liquid phase to the gas phase. There are two types of vaporization: evaporation and boiling.

Evaporation occurs at temperatures below the boiling point, and occurs on the liquid’s surface. For molecules of a liquid to evaporate, they must be located near the surface, be moving in the proper direction, and have sufficient kinetic energy to overcome intermolecular forces present in the liquid phase.

Boiling, by contrast, is a rapid vaporization that occurs at or above the boiling temperature and at or below the liquid’s surface.

Vapor Pressure

In much the same way that tea spreads out from a tea bag once the bag is immersed in water, molecules that are confined within a phase will tend to spread themselves (and the thermal energy they carry with them) as widely as possible. This fundamental law of nature is manifested in what is called the “escaping tendency” of the molecules from the phase. The escaping tendency is of fundamental importance in understanding all chemical equilibria and transformations.

It is possible to observe the tendency of molecules to escape into the gas phase from a solid or liquid by placing the substance in a closed, evacuated container connected to a manometer for measuring gas pressures

Answer 2

Answer:

i) physical state of the substance at A - Solid

physical state of the substance at C - Gas

ii) Melting point - 25°c

boiling point - 130°c

iii) À B` and C C`

iv) Condensation

v) the given substance is not water because of the following reason;

a) Melting point of water is ~ 0.1°c and here it is 25°c.

b) boiling point of water is 100°c