After condensation the water vapour or the moisture in the atmosphere takes one of the following forms — dew, frost, fog and clouds. Condensation takes place when the dew point is lower than the freezing point as well as higher than the freezing point.

noun. the act of condensing; the state of being condensed. the result of being made more compact or dense.

the act of increasing the density of something.

1. The report is a brilliant condensation of several years’work.
2. We get a lot of condensation on the walls in the winter.
3. His shaving mirror was covered with condensation.
4. There was a lot of condensation on the windows.
5. Poor air circulation can cause condensation.

Condensation is the process where water vapor becomes liquid. It is the reverse of evaporation, where liquid water becomes a vapor. Condensation happens one of two ways: Either the air is cooled to its dew point or it becomes so saturated with water vapor that it cannot hold any more water.

1 : the act or process of making more compact or concise. 2 : something that has been made more compact or concise a condensation of the story. 3 : the conversion of a vapor to a liquid (as by cooling)

Condensation: Dew, Fog, and Clouds. CHAPTER7. Condensation: Dew, Fog, and Clouds. Dew: the water droplets formed by condensation of water vapor on a relatively cold surface of an object. It forms when the temperature of an object drops below the dew point temperature.

Condensation happens one of two ways: Either the air is cooled to its dew point or it becomes so saturated with water vapor that it cannot hold any more water. Dew point is the temperature at which condensation happens. (Dew is simply condensed water in the atmosphere.)

In dropwise condensation the condensate liquid collects in the form of countless droplets of varying diameters on the condensing surface, instead of forming a continuous film, and does not wet the solid cooling surface.

The factors governing condensation

• The water vapour content of the air.
• Inside room temperature.
• Outside temperature.
• Internal and external temperature variation.

Removing energy (cooling) increases the rate of condensation This is because a lower temperature means that more molecules are moving more slowly. If molecules move slower, they are more likely to attract and change their state from a gas to a liquid.

When air rises into the low-pressure region of the upper troposphere, it expands. Because it is expanding without absorbing additional energy from its surroundings, it gets colder. If the air contains water vapor, the water vapor also gets cooler, which causes it to condense into tiny liquid droplets.

When gas molecules transfer their energy to something cooler, they slow down and their attractions cause them to bond to become a liquid. Making water vapor colder increases the rate of condensation. Increasing the concentration of water vapor in the air increases the rate of condensation.

Visible and Concealed Condensation Two things must be present for condensation to occur: warm moist air, and cool surface temperatures below the dew point. The proper control of these two factors can minimize condensation.

How does the temperature affect condensation? The amount of water vapor air can hold is directly related to the air temperature. Warmer air can hold more water vapor than cooler air. When warm air is cooled it looses its capacity to hold water vapor and, if it cools enough, it will begin to condensate.

The higher the vapor pressure, the faster the rate of condensation. Condensation occurs when a water vapor molecule collides with a liquid water surface, and chemically binds to liquid water molecules. It is very important to understand that the higher the air temperature, the higher the saturation vapor pressure.

(Also called adiabatic saturation pressure, adiabatic condensation pressure.) The pressure at which a parcel of moist unsaturated air expanded dry-adiabatically reaches saturation. See condensation temperature, lifting condensation level.

When atmospheric pressure increases, the boiling point becomes higher, and when atmospheric pressure decreases (as it does when elevation increases), the boiling point becomes lower. Solutes in the liquid phase also raise the equilibrium boiling temperature.

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So if you increase atmospheric pressure, the solution needs to exert greater amount of vapour pressure to boil. As mentioned earlier, you need to heat the liquid further so that the vapour pressure matches with the atmospheric pressure. Hence the boiling point increases.

Factors That Affect the Boiling Point

• Pressure: when the external pressure is: less than one atmosphere, the boiling point of the liquid is lower than its normal boiling point.
• Types of Molecules: the types of molecules that make up a liquid determine its boiling point.

Molecular composition, force of attraction and the presence of impurities can all affect the melting point of substances.

Boiling Point: The temperature at which the liquid boils and changes into gaseous state at the atmospheric pressure is called boiling point. For example, water boils at 100°C to form water vapour (at 76 cm pressure).

The boiling point of a liquid depends on temperature, atmospheric pressure, and the vapor pressure of the liquid. When the atmospheric pressure is equal to the vapor pressure of the liquid, boiling will begin.

The boiling points of alcohols are much higher than those of alkanes with similar molecular weights. Such a large difference in boiling points indicates that molecules of ethanol are attracted to one another much more strongly than are propane molecules.

Different liquids have different boiling points depending on the strength of bonding between the particles and the mass of the particles. The heavier the particles in the liquid, and the stronger the bonding, the higher the boiling point will be.

Melting point, temperature at which the solid and liquid forms of a pure substance can exist in equilibrium. As heat is applied to a solid, its temperature will increase until the melting point is reached. More heat then will convert the solid into a liquid with no temperature change.