Therefore the Na and Cl ions will be pulled apart and hydrated, meaning they will be surrounded by H 2 O molecules. Most hydrogen atoms consist of only 1 proton, but the isotopes deuterium and tritium have one and two neutrons in their nuclei respectively. 2 O due to the extra neutron in the deuterium nucleus. D 2 O can be produced through electrolysis and fractional distillation of water. It is used as a moderator of neutrons in nuclear power plants and in biological research as an isotopic tracer.
Ice occurs when water vapour or liquid water freeze.
Each H 2 O molecule forms hydrogen bonds with four neighbouring molecules, creating a tetrahedral shape. An ice crystal is made up of rings of these tetrahedrons forming at various angles to each other. At first sight ice seems brittle and shatters like glass when it is struck. However it flows under low stresses over long periods of time or under high stresses where pressure stops the ice from splintering. This happens because the layers of ice crystal can glide over and past each other without the hydrogen bonds being broken.