When a lot of heat is put into a solid-state, It generally changes into its liquid state and then into its gaseous if more heat is provided. But some substances directly transform from their solid-state to their gaseous state. However, when a substance changes its phase, there are various factors like temperature, the pressure that causes this transition. Sublimation and deposition are two phases. Sublimation is a phase where a substance directly switches from the solid to the gas state, whereas in a deposition, the substance changes into the gaseous state without passing through the liquid state.
Sublimation vs Deposition
The difference between sublimation and deposition is that in sublimation, a substance changes from the solid to the gaseous state without passing through the liquid state, whereas, in deposition, the substance transforms into the solid state without going through the liquid phase.
Sublimation is a phase where a substance is changed into the gaseous state from its solid form without experiencing the liquid state. Though this process consumes a lot of heat, it does not alter the chemical combinations of that substance.
On the other hand, deposition is exactly the opposite of sublimation. In the deposition, the substance changes from the gas state to the solid-state without passing through the liquid phase. This process releases a lot of energy, unlike sublimation. However, both of these processes do not include a liquid phase.
Comparison Table Between Sublimation and Deposition
|Parameters of Comparison||Sublimation||Deposition|
|Definition||Sublimation is a phase transition where a substance transforms from the solid state to the gaseous state without going through the liquid state.||On the other hand, deposition is exactly the opposite. In this process, the substance changes from the gas state to the solid-state without passing through the liquid state.|
|Purpose||Sublimation is used to break chemical compounds of substances so that their purified state can be achieved.||This process is used to make ice from evaporated water.|
|Consumption of energy||Sublimation consumes a lot of energy in the process but the chemical compounds of the substance remain intact.||Unlike sublimation, deposition releases a lot of energy.|
|Process||In sublimation, a substance transforms into the gaseous state from its solid state.||But in deposition, the process is reversed. The substance is not solidified but changes into its gaseous form.|
|Heat||Since this process releases a lot of heat, it is called an endothermic process.||In this process, a lot of heat is released. Thus, it is called an exothermic process.|
What is Sublimation?
Sublimation is a type of phase transition where a solid substance changes its form and becomes gas without passing through the liquid state. It is an endothermic process. An endothermic reaction is a chemical reaction where more energy is required to consume heat. A constant input of energy in the form of heat is often needed to keep an endothermic reaction going.
Dry ice is an example of sublimation. Dry ice is solid carbon dioxide. It can be seen that when the carbon dioxide is exposed to room temperature, it will go straight from its solid state to gas. Camphor, Naphthalene, Ammonium Chloride, Anthracene are examples of such substances that do not pass through a liquid state. Sublimation is the process where the substance is converted from its solid state to its gaseous form.
This process can be used to separate a few components of a chemical mixture. In a china dish, a mixture of ammonium chloride and salt is taken, and also an inverted fannel is positioned on top of that. The fannel should be closed with something like cotton. Then heat would be given from a burner to the mixture. As a result, ammonium chloride will start releasing vapor, but the salt will not. And the vaporized substance would be solidified.
What is Deposition?
A deposition is also a phase change where an object changes from its gaseous state to its solid form without passing through the liquid state. It is a reversed process of sublimation. So it is called de-sublimation.
It is an exothermic process as this reaction releases a lot of energy or heat. When a gas is cooled down, it usually converts into liquid and then into a solid-state. But in this method, the substance does not change into a liquid state.
But there are a few objects that directly convert into their solid-state from their gaseous form. As observed in the sublimation process, solid ammonium chloride has been transformed into fumes without entering its liquid form. When the heat of the burner is turned off, it can be seen that the vaporized ammonium chloride returns to its solid form without changing itself into liquid.
Main Differences Between Sublimation and Deposition
- In sublimation, an object changes from its solid state to its gas form. In the deposition, a gaseous object is transformed into its solid-state.
- Sublimation consumes a lot of energy as heat is needed on a large scale. But in deposition, the rate of releasing heat is high.
- Sublimation is an endothermic process, whereas deposition is an exothermic process.
- In sublimation, gas cannot be changed into a solid object. Similarly, in deposition, a solid substance cannot be altered into a gas.
- The method of sublimation is utilized to separate chemical components of an unpurified compound. On the other hand, deposition is needed to make ice.
In both sublimation and deposition, substances do not enter their liquified forms. However, there are many differences in both of the processes. In sublimation, a solid directly changes into vapor without passing through the liquid state, whereas in deposition, a gas directly changes into a solid without entering the liquid stage. The former is an endothermic process, whereas the latter is an exothermic process.
Thus, in sublimation, a solid changes into a vapor, and in deposition, vapor changes into a solid. Though these processes have a lot in common, the stages of the substances at the conversion ends are different.