The main difference between Vapor and Steam is that the Vapor is a a substance in the gas phase at a temperature lower than its critical point and water in the gas phase, which is formed when water boils. Steam is invisible; however, “steam” often refers to wet steam, the visible mist or aerosol of water droplets formed as this water vapour condenses
In physics a vapor (American) or vapour (British and Canadian) is a substance in the gas phase at a temperature lower than its critical temperature, which means that the vapor can be condensed to a liquid by increasing the pressure on it without reducing the temperature. A vapor is different from an aerosol. An aerosol is a suspension of tiny particles of liquid, solid, or both within a gas.
For example, water has a critical temperature of 647 K (374 °C; 705 °F), which is the highest temperature at which liquid water can exist. In the atmosphere at ordinary temperatures, therefore, gaseous water (known as water vapor) will condense into a liquid if its partial pressure is increased sufficiently.
A vapor may co-exist with a liquid (or a solid). When this is true, the two phases will be in equilibrium, and the gas-partial pressure will be equal to the equilibrium vapor pressure of the liquid (or solid).
Steam is water in the gas phase, which is formed when water boils or evaporates. Steam is invisible; however, “steam” often refers to wet steam, the visible mist or aerosol of water droplets formed as this water vapour condenses. At lower pressures, such as in the upper atmosphere or at the top of high mountains, water boils at a lower temperature than the nominal 100 °C (212 °F) at standard pressure. If heated further it becomes superheated steam.
The enthalpy of vaporization is the energy required to turn water into the gaseous form when it increases in volume by 1,700 times at standard temperature and pressure; this change in volume can be converted into mechanical work by steam engines such as reciprocating piston type engines and steam turbines, which are a sub-group of steam engines. Piston type steam engines played a central role to the Industrial Revolution and modern steam turbines are used to generate more than 80% of the world’s electricity. If liquid water comes in contact with a very hot surface or depressurizes quickly below its vapor pressure, it can create a steam explosion.
Cloudy diffused matter such as mist, steam or fumes suspended in the air.
The gaseous state of a substance that is normally a solid or liquid.
To become vapor; to be emitted or circulated as vapor.
To turn into vapor.
To use insubstantial language; to boast or bluster.
The vapor formed when water changes from liquid phase to gas phase.
Pressurized water vapour used for heating, cooking, or to provide mechanical energy.
Internal energy for motive power.
“After three weeks in bed he was finally able to sit up under his own steam.”
“Dad had to go outside to blow off some steam.”
A steam-powered vehicle.
Travel by means of a steam-powered vehicle.
Fencing without the use of any electric equipment.
To cook with steam.
To expose to the action of steam; to apply steam to for softening, dressing, or preparing.
“to steam wood or cloth”
To produce or vent steam.
To rise in vapour; to issue, or pass off, as vapour.
To become angry; to fume; to be incensed.
To make angry.
“It really steams me to see her treat him like that.”
To be covered with condensed water vapor.
“With all the heavy breathing going on the windows were quickly steamed in the car.”
To travel by means of steam power.
“We steamed around the Mediterranean.”
To move with great or excessive purposefulness.
“If he heard of anyone picking the fruit he would steam off and lecture them.”
Old-fashioned; from before the digital age.
the vapour into which water is converted when heated, forming a white mist of minute water droplets in the air
“a cloud of steam”
“she wiped the steam off the mirror”
“steam was rising from the mugs of coffee”
the invisible gaseous form of water, formed by boiling, from which this vapour condenses.
the expansive force of steam used as a source of power for machines
“a steam locomotive”
“the equipment was originally powered by steam”
locomotives and railway systems powered by steam
“we were trainspotters in the last years of steam”
energy and momentum or impetus
“the anti-corruption drive gathered steam”
give off or produce steam
“a mug of coffee was steaming at her elbow”
become or cause something to become covered or misted over with steam
“the warm air had begun to steam up the windows”
“the glass keeps steaming up”
cook (food) by heating it in steam from boiling water
“steam the vegetables until just tender”
(of food) cook by heating in steam
“leave the mussels to steam”
clean or otherwise treat with steam
“he steamed his shirts to remove the odour”
apply steam to (something fixed with adhesive) so as to open or loosen it
“he’d steamed the letter open and then resealed it”
(of a ship or train) travel somewhere under steam power
“the 11.54 steamed into the station”
come, go, or move somewhere rapidly or in a forceful way
“Jeremy steamed in ten minutes late”
“the company has steamed ahead with its investment programme”
start or join a fight
“he’ll be the one to throw the first punch, then run to the back when the others steam in”
(of a gang of thieves) move rapidly through a public place, stealing things or robbing people on the way
“steaming is not restricted to tube trains”
generate steam in and operate (a steam locomotive)
“you can learn the intricacies of steaming a locomotive for the first time”
be or become extremely agitated or angry
“you got all steamed up over nothing!”
“after steaming behind the closed door in his office, he came out and screamed at her”