The universe is known for its ability to undergo many physical and chemical processes to keep its balance and manage life on earth. Hence, these changes are absolutely essential to keep the breathing creatures alive. Hence, general chemistry becomes inevitable for people to understand to make sense of the changes that are undergoing.
Two such processes are evaporation and sublimation heat transfer process, which are often confused by students. Although both of them are endothermic reactions, there still lie considerable differences you need to know to pass the exam. Here are some common differences between evaporation and sublimation that can guide you to get conceptual clarity and understand the mechanism of the state of matter.
What is the Difference Between Evaporation and Sublimation?
What is Sublimation?
Sublimation can be defined as the transition of matter from solid to gas (with no liquid state). Similarly, the molecules are transforming the chemical bonds of the material and releasing them into the air. Hence, as it requires a large amount of energy, this entire process is endothermic. Also, the energy in this process is calculated as enthalpy.
Another point important to consider here is that it occurs at low pressure and temperature (the triple point of the substance), making the process fast enough. This is primarily because as the temperature increases, the solid immediately changes its direction to a gas. Here, an example of this process would be turning dry ice into gas carbon dioxide.
What is Evaporation?
In simple words, evaporation is defined as the transfer of liquid matter into a gaseous state. This is an example of an endothermic process where all the intermolecular forces are in play and these are broken down into the vapors. Likewise, the process is directly proportional to the temperature. Thereby, to start the process, you will have to increase the overall heat. Here are some factors that influence the process of evaporation;
• Large surface area is needed for the operation of the process.
• High concentration of air can disturb the evaporation process.
• A high flow of air increases the speed of evaporation.
• If the intermolecular forces are stronger in the process, the enthalpy of the evaporation is high.
Sublimation vs. evaporation
Here are some key differences between vaporization and sublimation;
• In the process of sublimation, the solid-state changes into the gaseous state, and hence, there is no liquid matter state. In contrast, the evaporation process undergoes contrasting stages of matter, from liquid to gas.
• In the sublimation process, the initial phase of the matter is solid. In contrast, the initial stage is liquid in the evaporation process.
• The sublimation process has all the energy emission that is required to start the process. On the other hand, the evaporation process only gives the enthalpy that is needed for the entire procedure.
• In the sublimation process, the phase change occurs from the solid stage to the gas at low pressure and temperature (it is preferred to keep it below the triple point of the substance). On the contrary, in the evaporation process, the phase occurs from liquid to gas on the surface of the liquid with a reasonable temperature range.
• An example of the sublimation process is naphthalene while the evaporation process is the transfer of liquid water into vapors. Now you can easily understand what is the difference between evaporation and sublimation.
There are some similarities between sublimation and evaporation.
- Both processes are endothermic
- At the end of the process both sublimation and Evaporation produce gas
- In both processes intermolecular forces break dwon to produce molecules
What is taking place during the process of sublimation?
In simple words, the transition of solid matter into a gaseous state, without going into liquid form is known as the process of sublimation. This process involves a high amount of energy, making it an endothermic process. It also demands a high temperature, so that it directly uses all the heat to convert solid into a gas. Here, an example of this process would be turning dry ice into gas carbon dioxide.
What is the sublimation point?
A sublimation point is defined as the temperature at which the solid-state of the compound is broken down into smaller particles. This point also changes the chemical bonds of the substances and changes them into gas. For instance, at 1 atm, the solid CO2 changes into vapors, while keeping the triple temperature intact. Here, -78.5 degrees Celcius is the sublimation point.
Why is sublimation endothermic?
Sublimation is a process that transforms the solid state of matter into its gaseous state at a high-temperature point. It involves absorption of heat as it provides needed energy to break the molecules that in return, changes the chemical bonds of the substance. Hence, the alternate forces allow the molecules to escape into the gaseous state or vapors. Likewise, all the phase changes in the evaporation and sublimation process are undergoing some change, making them an endothermic process.
How are evaporation and sublimation similar?
Both of these processes are similar, primarily because the phase changes the substance into the gaseous state of matter. Similarly, as energy is required for both the processes at a needed temperature, the heat is being absorbed through phase changes. Therefore, both the processes are endothermic and go through similar phase changes.
Now hopefully you have got the Difference between Evaporation and Sublimation. In the end, matter exists in different forms that undergo considerable changes, making the observers confused and puzzled for the most part. These changes are the results of the chemical and physical reactions naturally occurring on the earth. Such are the processes of evaporation and sublimation that are being misinterpreted by many. This is primarily because both these changes are endothermic. Yet, don’t worry as this guide on sublimation vs. evaporation can help you get conceptual clarity.