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23 Ιουν 2023 · Two computer images of the structure of ice. The water molecules have been arranged, so that each oxygen atom is surrounded by four hydrogen atoms in tetrahedral geometry. Two of these atoms are covalently bound to oxygen, while the other two are hydrogen bonding with the oxygen.
- 7.3: Hydrogen-Bonding and Water
Identify three special properties of water that make it...
- 7.3: Hydrogen-Bonding and Water
13 Νοε 2022 · Identify three special properties of water that make it unusual for a molecule of its size, and explain how these result from hydrogen bonding. Explain what is meant by hydrogen bonding and the molecular structural features that bring it about.
6 Μαΐ 2018 · Water has stronger hydrogen bonds than ice does. Liquid water is denser than ice. Since water and ice are both made of H2O molecules, the fact that water is denser means the H2O molecules are closer together in water than they are in ice.
3 Ιαν 2012 · Water has high melting and boiling points which is caused by the strong intermolecular forces of hydrogen bonding between the molecules. In ice (solid H 2 O) and water (liquid H 2 O) the molecules are tightly held together by hydrogen bonds.
Hydrogen bonds in Ice. In ice Ih, each water forms four hydrogen bonds with O---O distances of 2.76 Angstroms to the nearest oxygen neighbor. The O-O-O angles are 109 degrees, typical of a tetrahedrally coordinated lattice structure. The density of ice Ih is 0.931 gm/cubic cm.
In ice (right), the hydrogen bonds become permanent, resulting in an interconnected hexagonally-shaped framework of molecules. Ice is less dense than liquid water and so it floats. Ponds or lakes begin to freeze at the surface, closer to the cold air.
Hydrogen bonds have about a tenth of the strength of an average covalent bond, and are being constantly broken and reformed in liquid water. If you liken the covalent bond between the oxygen and hydrogen to a stable marriage, the hydrogen bond has "just good friends" status. Water as a "perfect" example of hydrogen bonding.
