Water uniqueness

Liquid water is difficult to find in the universe. Scientists have found frozen ice in places such as Mars and gaseous water vapor in atmospheres such as that on Venus. However, no one has been able to find liquid water anywhere other than on Earth. Water is the only natural substance that is found in all three states of matter (solid, liquid, and gas) at the temperatures normally found on Earth. By exploring a few of the properties of water, you will discover what makes water unique. 

Drying, the removal of water, is a special problem because water is a unique compound and there is a lot of it around. The features which together make water unique include a high dipole moment and polarisability, its amphoteric character, its ability to act as donor and acceptor in hydrogen bond formation, and its smallness. 

Narayan, S., H. Muldoon, M.G. Finn, V.V. Fokin, H.C. Kolb and K.B. Sharpless, On Water Unique Reactivity of Organic Compounds in Aqueous Suspension, Angewandte Chemie International Edition, 44, 3275-3279 (2005). 

What force gives water unique properties ... 

Water is the major component of all living organisms. It constitutes 60% or more of the weight of most living things, and it pervades all portions of every cell. It existed on our planet long before the appearance of any form of life. The evolution of life was doubtlessly shaped by physical and chemical properties of the aqueous environment. All aspects of living cells structure and function seem to be adapted to water-unique properties. 

Surfaces adsorbing a minimal amount of protein are important in many applications such as blood-contacting devices, membrane separators, sensors, and contact lenses. Therefore, much effort has been expended on minimizing or eliminating protein adsorption. To prevent protein adsorption, the utilization of water-solnble polymers such as polyacrylamide, poly(A -vinyl-2-pyrrohdone), and PEO has been considered. In particular, PEO has a low interfacial free energy with water, unique solution properties, molecular conformation in aqueous solution, high surface mobility, and steric stabilization effects [38,39] (Figure 11.5). 

In what ways is water unique What about the water molecule causes the unique properties of water ... 

Narayan S et al (2005) "On water" unique reactivity of organic compounds in aqueous suspension. Angew Chem hit Ed 44 3275-3279... 

Water is one of the basic elements for life. It is even assumed that the evolution of life is only possible if there is liquid water present. A water molecule has some remarkable properties that make it quite unique in the universe. In the first chapter of this book we will review these basic properties of water and the role of water on Earth. All ancient civilizations realized the importance of water and their cities were constructed near great reservoirs of water. But is water unique on Earth Do we find water elsewhere in the solar system, on extrasolar planetary systems or in distant galaxies We will start the search for the presence of extraterrestrial water in our solar system. Surprisingly enough it seems that water in some form and sometimes in only minute quantities is found on any object in the solar system. Even on the planet nearest to the Sun, Mercury, there may be some water in the form of ice near its poles where never the light of Sun heats the surface. And there are objects in the solar system that are made up of a large quantity of water in terms of their mass, like comets and several satellites of the giant planets. 

---