How is steam different from gas?

Difference between gas and steam

Difference between 2021

Main difference: Ga it a state of matter. Steam is a state of equilibrium between a gas and a liquid, which can easily be converted into a liquid by applying pressure


Main difference: Gas is a state of matter. Vapor is a state of equilibrium between a gas and a liquid that can easily be converted into a liquid by applying pressure without changing the temperature.

Many people mistakenly consider gas and steam to be the same or similar. In technical terms, however, the two substances differ considerably. There are four states of matter; H. Four different forms in which things can exist: solid, liquid, gas and plasma. Solid is when things hold their shape and their molecules are closely linked. Liquid is when the molecules have a little more space between them so that matter is liquid and takes the shape of the container it is in. Gas is when the molecules have a lot of space between them so that they can move in different directions and expand constantly. Plasma is similar to gas but becomes ionized; H. The molecules are split into charged ions.

Steam is now different from all of these. It is mostly mistaken for a gas, which is good for everyday laypersons, but the two are scientifically different. The confusion arises from the fact that steam is very similar to a gas. Indeed, it is a gas; a gas that is constantly in transition between gas and liquid.

Technically, vapor is a gas that is below its critical temperature, which means that by increasing its pressure it can be condensed into a liquid without lowering the temperature. Another way of describing vapor is that it is a state of equilibrium between a gas and a liquid that can easily be converted to a liquid by the application of pressure without changing the temperature. Instead of a liquid, its natural state can also be solid.

An easier way to differentiate between the two is to suggest that a vapor is a gaseous substance, the temperature of which should normally be a liquid or a gas. A gas, on the other hand, is a substance whose temperature is normally a gas. Other than that, there is no significant difference between a gas and a vapor which is why it is so difficult to distinguish between the two. However, once something is known about the substance, i. H. Whether or not it should be a gas at a given temperature will make it easier to distinguish the two.

Let's consider an example:

Take a helium balloon and let all the air out. What is the result? It's helium gas. It is never considered vapor because it was gaseous inside the balloon and is still in deflation. Even though the pressure was inside and outside the balloon while the temperature stayed the same, helium hasn't changed, so it's a gas.

However, put some gasoline in a container. Now open the container. that smell is gasoline vapor. The reason this is a vapor, not a gas, is because inside the bottle it is a liquid, but it turns into a gaseous form the moment it is let out and the pressure on it changes . Now, if all the vapors could be collected and returned to the container, it would turn back to liquid due to the pressure exerted on it. However, the helium would still be a gas if put back into the balloon.

Comparison between gas and steam:



Definition (Oxford Dictionaries)

A gaseous substance that cannot be liquefied by the application of pressure alone.

A gaseous substance that is below its critical temperature and can therefore only be liquefied by pressure.


Is a state of matter

Vapor is a substance in a gaseous state - a state in which it is usually liquid or solid.

Physical states

One of the four fundamental states of matter, along with solid, liquid and plasma.

No state of matter. Equilibrium between two states of water, d. H. Gas and liquid or solid.

Natural state

At room temperature the gas would still be a gas in its natural state.

At room temperature, the natural state of the vapor would be either solid or liquid.

Phase change

In order to change the phase of a gas, one would have to change the temperature and the pressure.

Steam can be brought to its natural state simply by changing the pressure. The temperature does not need to be changed.

Physical Properties

Gases compress easily, expand to fill their containers, and take up much more space than liquids or solids. They don't have a clear shape under the microscope.

Vapor particles can have a specific shape when viewed under a microscope. They're also easier to compress because they're always in transition.

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