Evaporation and Distillation Definition, Differences, and Applications
The matter has three phases such as solid, liquid, and gaseous phases. These phases are interconvertible in nature. However, they have some processes that they need to undergo in order to be able to interconvert into the other. Evaporation allows a phase change from the liquid state to the gas state. This process also takes place in the environment commonly around us.
The most common example is the heat of the sun evaporating the water in the sea or rivers into vapors. Unlike evaporation, the distillation process is not something that occurs naturally; it needs external energy to be provided in order to take place. In this process, there is the change of gases back to liquid.
What are Evaporation and Distillation?
Evaporation is described as a type of vaporization method that occurs on the liquid's surface as it changes into the gas phase. The gas that is surrounded must not be saturated with the evaporating substance. The liquid molecules transfer energy to each other when they collide, depending on how they collide. When a molecule available near the surface absorbs enough energy to overcome the vapor pressure, it will escape and enter into the surrounding air in the form of gas. When evaporation occurred, the energy which has been removed from the vaporized liquid will reduce the liquid temperature, resulting in evaporative cooling.
On average, only a fraction of the liquid molecules has enough heat energy to escape from the vaporized liquid. This evaporation will continue until an equilibrium is reached when the liquid evaporation becomes equal to its condensation. Throughout the enclosed environment, a liquid will be evaporated until the surrounding air is saturated.
Evaporation
Evaporation is a necessary component of the water cycle. Solar energy (sun) drives the evaporation of water from water resources such as lakes, oceans, soil moisture, and other sources of water. In hydrology, it is said that evaporation and transpiration (which involves evaporation within the plant stomata) are collectively termed evapotranspiration. Water evaporation takes place when the surface of the liquid gets exposed by allowing the molecules to escape and form water vapor. Then, this vapor can rise and then form clouds. The liquid will turn into vapor having sufficient energy.
Applications of Evaporation
Industrial applications include most coating and printing processes. These include drying a variety of materials such as paper, lumber, cloth, and other chemicals, and recovering salts from solutions.
The evaporation used to concentrate or dry samples is a common preparatory step for most laboratory analyses like chromatography and spectroscopy. These systems include centrifugal evaporators and rotary evaporators.
If clothes are hanging on the laundry line, even though the ambient temperature falls below the water boiling point, water evaporates. This is accelerated by factors including heat from the sun, low humidity, and wind. Hot air is blown through the clothes in a clothes dryer, allowing water to evaporate rapidly.
A traditional Indian porous clay container called Matki/Matka is used to cool and store water and other liquids.
A traditional Spanish porous clay container called Botijo, designed to cool the contained water by the evaporation process.
Evaporative coolers can cool a building significantly by merely blowing dry air over a filter saturated with water.
Distillation
The process of separating the substances or components from a liquid mixture by using selective condensation and boiling refers to distillation. Essentially, distillation can result in a partial separation or a complete separation (approximately pure components), that increases the concentration of the selected component present in the mixture. In the other case, the method exploits differences in the relative volatility of the mixture's components. Considering industrial chemistry, distillation is a unit operation practically of universal importance. Still, it is a process of physical separation, not a chemical reaction.
Applications of Distillation
The distillation of fermented products forms distilled beverages with a strong alcohol content or separates certain other fermentation products having commercial value.
Distillation is a traditional and effective method of desalination.
Oil stabilization is a kind of partial distillation in the petroleum industry, that lowers the vapor pressure of crude oil, making it safe, thereby for transport and storage, and reducing the atmospheric emissions of volatile hydrocarbons. In oil refineries midstream operations, fractional distillation is a primary operational class for converting crude oil into fuels and also chemical feedstocks.
Cryogenic distillation tends to separate air into its components, notably oxygen, argon, and nitrogen for industrial use.
Huge amounts of crude liquid products of chemical synthesis in the chemical industry are processed to separate them from the impurities, unreacted starting materials, or other products.
To discuss briefly, there is much difference between evaporation and distillation. A few of them are tabulated below.
Difference Between Evaporation and Distillation
From the above-tabulated difference between evaporation and distillation, it can conclude that the primary difference between them lies at the boiling point. Evaporation occurs below the liquid boiling point, whereas distillation occurs right at the boiling point. Both processes depend on certain factors that may be the same, but considering all the cases, they are vastly different.
Examples of the Evaporation process
The rain cycle is one of the most common examples of the evaporation process. This process involves two cycles where the first cycle involves evaporation of the water from water bodies and the second part of the cycle where the vapors condense to form the liquid. The colder the temperature tends to be, the faster the condensation that takes place.
FAQs on Difference Between Evaporation and Distillation for JEE Main 2024
1. Explain Distillation vs. Evaporation?
To brief on Distillation vs. Evaporation considering some special factors, we can say as below.
Features Differences
The evaporation process happens only at the liquid surface, whereas the distillation process doesn’t only happen at the surface of liquids.
Boiling Point Differences
In the evaporation process, the liquid vaporizes below its boiling point. But, on the contrary of the distillation process, the liquid vaporizes at its boiling point.
Duration of the Process Differences
The evaporation process is gradual and slow; besides, the distillation process is rapid or quick.
2. What is the Key Difference Between Distillation and Evaporation?
Some of the key differences between Distillation and Evaporation are given below.
In the distillation process, when the liquid reaches the boiling point, it forms bubbles. However, in the evaporation process, the bubbles do not form any bubbles because the liquid doesn’t reach the boiling point.
The distillation process is used for purification and separation of a liquid. However, evaporation isn’t so necessary.
In the distillation process, heat energy is required to be supplied to the liquid molecules. So that the liquid molecules will go into the vapor state. However, considering the evaporation, there is no need to supply external heat energy. The molecules instead get energized when they collide with each other during the process. The same energy is then used to release the molecules into the vapor state.
3. What are the different types of distillation methods?
There are different types of distillation methods that can be used. They can be given as follows:
1. Simple distillation method:
This is used to separate about two or three liquids that have a significant boiling point gap. The components of the liquid mixture are separated when they start to boil at their own respective boiling points and then change into their vapor phase. The vapor is then further condensed and collected.
2. Fractional Distillation:
A fractionating column is used to separate two miscible liquids which have very close boiling points.
3. Steam distillation:
In steam distillation, the separation is carried out by using steam for those liquids which are immiscible with water. When such compounds are mixed along with steam they tend to vaporize much faster than their usual boiling point.
4. What are some of the notable differences between evaporation and distillation?
The notable differences between evaporation and distillation can be provided as follows:
In the process that involves distillation when the liquid tends to reach boiling point, It starts forming bubbles. However, in evaporation, there is no bubble formation; they just give out vapors.
Distillation is a process used for the separation and purification of a liquid. However, evaporation is not a process that is specifically used for this purpose.
Evaporation can be done naturally while distillation needs to be set up and created. Distillation can only take place in a laboratory using all the pieces of equipment needed for distillation.
5. What are some examples of distillation?
Distillation is quite an important procedure that is used in chemistry labs for various commercial purposes some of the examples of distillation can be provided as follows:
Salted water can be purified into water that can be used in houses for various purposes.
Highly used in alcoholic beverage production.
Fuels and gasoline are separated from impurities or crude oil that is present by using distillation in petroleum industries.
Air can be differentiated into its various components such as nitrogen, oxygen, and argon for commercial uses.
6. What is the process involved in distillation and why is it important to learn about the Difference Between Evaporation and Distillation?
The process of separating liquid is quite an important technique which is done by distillation. The process starts by boiling the liquid and then a collection of the vapor as and when it cools down takes place. This vapor that has cooled down will lead to liquid formation. The molecules tend to gain more energy and the vapor pressure is more than the atmospheric pressure. Due to the difference in pressure, the liquid vapors rise above the liquid level. This process of distillation will be very important in applications.
7. Which process is better to be used and why is it that distillation has an advantage over evaporation?
Evaporation is not a method that is used for separation; instead, it is a process where the liquid substance changes into a gas by changing its state of matter. It is hence a change seen not in the formula of the substance but in the physical property. On the other hand, distillation is a type of method used to collect a significant liquid from a mixture of at least 2 or more liquids. Here distillation has a much better advantage than evaporation because they tend to provide the desired substance without evaporating it which might be a risk in evaporation methods.
