Water Text

Properties of Water

Water is the basic solvent of life.
If water did not hydrogen bond (Fig. A.), it would be a gas at room temperature.
At room temperature, 5 to 7 water molecules will be hydrogen bonded at any one instant. Such bonds are continually being formed and broken due to the thermal motion of the molecules. View "water box" in three dimensions (Note: to view this interactively on your Web browser, the free Chemscape Chime plug-in viewer must be installed in your browser's plug-in folder.)
As water temperatures drop, the thermal motion that disrupts hydrogen bonding is decreased and more water molecules will be momentarily bound together.
As water freezes all the molecules are bound together in a hydrogen bonded lattice that we call ice. (Note: to view this interactively on your Web browser, the free Chemscape Chime plug-in viewer must be installed in your browser's plug-in folder.)
Because of the polar nature of water molecules they will tend to cluster around ions. The electronegative domain of water will be attracted to the positive ions and the electropositive domain the negative ions (Fig. B.).
Molecules that can hydrogen bond to water tend to be more soluble in aqueous solutions than those that do not hydrogen bond (Fig. C.).
Molecules that can interact with water are called hydrophillic (water loving).
Nonpolar molecules do not interact with water and are considered hydrophobic (water fearing). Hydrogen bonded water molecules tend to form ice-like cages, called "clathrate structures" around such molecules (Fig. D.).