How does Water exist in Air?

Water molecules in the air exist like sand, salt and sugar molecules exist in a salt-sand-sugar mixture. The compound H2O is free and stands alone like a component in a physical mixture not as a component in a chemical mixture
A mechanical Mixture

Each component stands apart
Source - tojojoling.blogspot.com

Each piece stands apart
Source - cookteen.com

In a mechanical mixture, each component exists separately from every other component.
In a mechanical mixture, each component can be separated from all other components through a process akin to separating all the pasta or the red candy.
Air is a mechanical mixture of elements and compounds
Elements in the air include:

Gas	Ratio compared to Dry Air (%)		Chemical Symbol
	By volume	By weight
Oxygen	20.95	23.20	O2
Nitrogen	78.09	75.47	N2
Hydrogen	0.00005	~ 0	H2
Argon	0.933	1.28	Ar
Neon	0.0018	0.0012	Ne
Helium	0.0005	0.00007	He
Krypton	0.0001	0.0003	Kr
Xenon	9 10-6	0.00004	Xe

Source - http://www.engineeringtoolbox.com/air-composition-d_212.html
Compounds in the air include:
Water, Carbon Dioxide, Sulfur dioxide, Methane, Nitrous oxide, Ozone, Nitrogen dioxide, Iodine, Carbon monoxide and Ammonia
Water exists in the air in 2 forms
The water in air exists in two states: about 2% exists in liquid form while the remaining approx 98% exists in liquid form.
The task of extracting water from the air is mostly a task of extracting the vapor form of water from the air.