Difference Between Vapor vs Gas
As a science student, you probably know that matter has four states. These structures include solid, liquid, gas, and plasma. While many students do not seem to have any challenges distinguishing the dissimilarities among the four of them, the same cannot be said of the difference between vapor and gas.
The reason is that the two concepts tend to share many similarities, making it confusing. But in spite of the resemblance, they have key disparities. So, in this well-researched guide, you will learn the definitions of the two terms, the contrasts, and everything in between. Now, we will kick it off with the definitions.
Definition of Vapor
Vapor is a gas and liquid mixture. Indeed, matter exists in that phase and may contain the same number of molecules as a liquid. It is formed as a result of change and can even undergo further alterations. When something exists in this nature, it is regarded as a multiphasic substance. Well, that substance is said to have the same structure as gas.
However, the vapor-to-liquid transition that happens to it is known as condensation. This phase is actually possible because its temperature is lower than the critical point of the element in question. Noteworthy is that the critical point of the matter is the temperature and pressure where it is hard to distinguish between liquid and gas.
However, only gaseous compounds can exist above that critical temperature. Hence, gas does not coexist with a liquid above a certain temperature. A good example is steam that exists as vapor when high heat is applied but becomes liquid after the heat is removed. The difference between gas and vapor will make more sense if we discuss the former.
Definition of Gas
Gas is the state of matter where molecules are always moving. The content does not have strong bonds keeping them together. Hence, they move from one place to another. According to the scientific explanation, an atom in a gaseous nature has kinetic energy that is beyond normal, leading to their random movement.
When the gaseous substance is cooled to a relatively low temperature, there may be a change of form. A good example is nitrogen that can be chilled to zero Celsius, thus condensing into a liquid. Interestingly enough, fluid-like nitrogen has many different applications including its use to eliminate minor skin sores.
Another example that readily comes to mind is carbon dioxide that can be cooled to turn it from a gas to a liquid form. When it is further cooled to a solid condition, carbon dioxide is known as dry ice.
When gas exists naturally, it is said to be in a thermodynamic state. It only experiences an alteration when certain conditions are applied as in the case of carbon dioxide. So, this explains why it is called a monophasic substance.
Main Differences Between Vapor vs Gas
Now, let us shed more light on the vapor vs gas concept.
| Basis of Comparison | Gas | Vapor |
| Meaning | An atom, element, or anything that may or may not be visible and is in constant motion while taking on an air-like appearance | Anything with a liquid and gas mixture whose appearance can easily be changed, depending on the prevailing circumstances |
| State | Exists in a shape known as thermodynamic state | Exists as a liquid and solid mixture |
| Nature | One of the primary forms of something | A temporary state of a compound that appears as the liquid/gas interface |
| Stability | It is in random motion and disperses whenever there is an alteration in equilibrium | It is relatively stable even if the equilibrium state is altered |
| Origin | It is in its natural fashion or origin | This is a type of gas resulting from a mixture with liquid or solid, so it is not the original form |
Difference Between Vapor and Gas: Conclusion
In conclusion, you need to understand that this guide on gas vs vapor is incomplete without mentioning the key contrasts between them. While the former is in its natural structure, the latter is a temporary phase that is easily altered.
A good example is steam that can return to liquid when heat is removed. However, steam exhibits the properties of a gas when it is still hot. Finally, this guide has explained the primary contrasts between the two concepts.
