Why does the temperature remain constant during a change of state (phase transition)? During a change of the state of matter, the supplied energy is not used to increase the kinetic energy of the molecules, but to change the binding energies. Therefore, the temperature remains constant.

The heat is used to break the bonds between the ice molecules as they turn into a liquid phase. Since the average kinetic energy of the molecules does not change at the moment of melting, the temperature of the molecules does not change.

Answer: During a phase change from say solid to liquid (fusion), the energy being put in the system is being used as work because the molecules are using that energy to break bonds. Until all the bonds are broken and the entire phase is converted, there is no heat change.

The extra heat supplied is used in the melting of ice which is called the latent heat of fusion. Similarly, when a liquid starts boiling the temperature of the liquid does not change instead of a continuous supply of heat. That’s why the temperature of a substance remains constant during its melting or boiling.

gases

Examples of Liquid to Gas (Vaporization) Water to steam – Water is vaporized when it is boiled on the stove to cook some pasta, and much of it forms into a thick steam. Water evaporates – Water evaporates from a puddle or a pool during a hot summer’s day.

But if we lower the temperature below 0 degrees Celsius, or 32 degrees Fahrenheit, water changes its phase into a solid called ice. Similarly, if we heat a volume of water above 100 degrees Celsius, or 212 degrees Fahrenheit, water changes its phase into a gas called water vapor.

Liquid helium boiling into gaseous helium. 4.) Mercury evaporating into… well, mercury fumes.

When you reach your boiling point, the molecules in your system have enough energy to become a gas. When the temperature drops, energy will be transferred out of your gas atoms into the colder environment. When you reach the temperature of the condensation point, you become a liquid.

Sublimation is the process of transformation directly from the solid phase to the gaseous phase, without passing through an intermediate liquid phase. At temperatures and pressures below those of the triple point, a phase change between the solid and gas phases can take place.

Hydrogen is a gas at STP and platinum is solid. Hence, Hydrogen gas adsorbed on the surface of platinum is an example of gas in solid solution.