Sublimation is the change in phase from a solid to a gas. It is important to note that no liquid phase is present in sublimation.Know More
Sublimation occurs at temperatures below a substance's 'triple point'. The triple point is an instant in which all three phases of matter exist in equilibrium. Triple points are represented on phase diagrams. In sublimation the solid substance is heated to a point at which it turns to gas without becoming a liquid first.
Sublimation is used to purify substances in chemical processes. Usually the practice begins by placing a solid in a vessel and then heating it within a vacuum. The pressure and heat volatilize the solid, converting the compound into a gas. The impurities remain a solid in the vessel.
Sublimation is applied to the functions of dyeing and freezing. In dyes, the ink is vaporized by a heater and then cooled on the paper or fabric. As a result the color transfer is highly-defined and more easily controlled, making more intricate dying possible.
In freezers a combination of sub-zero temperatures and dry, arid air prevent frost from forming on the inside. This is managed by an internal thermostat and fan. Iodine crystals and carbon dioxide are common examples of sublimation as they sublimate at room temperature.Learn more about States of Matter
A phase change, also known as a phase transition, is a transformation in the physical state of a certain sample of matter. The phrase is most commonly used to describe the transition of a material between solid, liquid, gaseous and plasma states.Full Answer >
Water freezing into ice is a physical change because the hydrogen and oxygen molecules that make up the water stay the same, despite the change in state from liquid to solid. A physical change is simply a change in the material's physical properties, such as shape or phase.Full Answer >
Heat provides the energy needed to change a solid into a liquid. Heat energy is added to break the bonds between molecules in a solid. The amount of heat needed to cause a solid to turn to a liquid is called the melting point.Full Answer >
A solid can turn directly into a gas through a process called sublimation. In this instance, the solid vaporizes without going through the intermediary liquid stage. For example, in the water cycle, this would involve snow or ice turning directly into water vapor without going through the melting process. The opposite process, in which vapor changes into ice, is known as deposition.Full Answer >