Vapor vs Steam
Both vapor and steam are classified as invisible and odorless. The main difference is that vapor is any substance in a gaseous state. Vapor is a type of gas while steam, in return, is a type of vapor. Apart from steam, many examples of vapor include gasoline, various chemicals, and chemical applications like cleaning products and many others.
Vapor connotes two states of matter with gas as one constant in a particular substance. It also connotes some form of transformation from one state to another. To put it simply, a solid or liquid substance can change into gas, and that resulting gas is called a vapor. On the other hand, steam is a technical term for water vapor or water in a gaseous state. It is also one of the most common examples of a vapor.
The key difference between vapor and steam is that the former term is a generally used term while steam is the technical and specific term. A shared attribute between vapor and steam is the point of origin or how it is formed. Steam and other kinds of vapor are often made by evaporation or with other means or application of heat. Another similarity is their characteristics like being suspended in air, being in a diffused state, and being a result of a process.
Because a vapor is a general term, there are many concepts that allude to it. Terms like saturated vapor (vapor in the boiling point temperature), the types of vapors which do not follow the general gas laws (which include the wet saturated vapor and dry saturated vapor) and superheated vapor (vapor with no liquid particles but its temperature past the boiling point of the substance) are often used to indicate the state of vaporization of a substance.
Wet saturated vapor is defined as vapor with suspended liquid particles while dry saturated vapor is a type of vapor with no liquid particle.
On the other hand, steam directly means water in a gaseous state. Steam is created due to the method of evaporation or sublimation and eliminated by condensation. It contains very tiny amounts of water. In evaporation, heat is an essential factor in making steam or water vapor, while in condensation, water vapor actually becomes visible usually in the form of clouds or a “mixing cloud.”
People often mistake the air or the visible escaping cloud as steam. However, technically, it is not steam but a “mixing cloud.” Steam is created during evaporation (like boiling a kettle of water) but it is never visible. A “mixing cloud” is created when the heated water vapor from the boiling kettle mixes with the cool surrounding water vapor in the environment. The “mixing cloud” becomes visible because of the mix or contact of hot and cool water vapors. The “cloud” is already in a condensed form and takes on a foggy appearance like clouds in the sky. The tiny water droplets in the cool water vapor reflect on the light and make it visible to the eye.
There are also two types of steam: “wet” steam and “dry” steam. “Wet” steam is a type of steam created by boiling liquid water to its boiling point (1000C or 212 F) or in a greater temperature. “Dry” steam is steam occurring and exiting under the temperature of water’s boiling point.
Summary:
1.Vapor and steam are related terms. “Vapor” is a group term for any substance (solid or liquid) that undergoes a gaseous state while “steam” is a specific term that denotes liquid in a gaseous state). In terms of hierarchy, “gas” is the broadest category followed by “vapor” as one of its types and, in return, followed by steam as a type of vapor.
2.Since steam falls under vapor, most of the steam’s characteristics like being odorless, invisible, and diffused are reminiscent of vapor. Also, the creation of both occurrences requires heat and a certain thermal condition like the boiling point and temperature.