What is Heavy Water?

Water is a rare and precious natural resource. Water is necessary for all living things to survive. Water is so important to us that we can’t conceive a world without it. Animals and plants both require water to accomplish their daily metabolic operations. The photosynthesis process requires water for plants to produce their sustenance. We can all spend days without food, but we can’t conceive surviving days without water; plants, too, dry out and shed their leaves without it.

Heavy Water

Heavy water, with the formula D2O, is another type of water. It’s a little thicker than regular water, and it’s blue and tasteless. Heavy water is also known as deuterium oxide. The hydrogen isotope denoted by the letters D or H2 is the hydrogen isotope. Ordinary water is denoted by H2O, whereas heavy water is denoted by D2O.

When two hydrogen atoms in regular water are replaced by deuterium atoms, heavy water is formed. Chemically, deuterium oxide, or D2O, is heavy water.

The discovery of heavy water is credited to Urey. One part of heavy water is found in every 6000 parts of ordinary water. Lewis and Donald used continuous electrolysis to recover a few ml of pure heavy water out of water containing a trace amount of alkali. It was discovered in the Himalayas, among the melted snow leftovers. Miniscule levels have also been found on the leaves of Banyan trees and in rainfall.

Properties of Heavy Water

Heavy water, like regular water, is a colorless, odorless, and tasteless portable liquid. The physical properties of water and heavy water are listed below.

• Because heavy water has a higher molecular weight (20 g) than water (18 g), its boiling and freezing points, specific heat, density, viscosity, temperature of maximum density, and latent heat of vaporization are all higher in heavy water than in water.
• The dielectric constant of heavy water, on the other hand, is smaller than that of water.
• As a result, ionic compounds dissolved in heavy water have a lower solubility than those dissolved in water.

Chemical Properties of Heavy Water

Heavy water can participate in any chemical reaction that water can. Heavy water, on the other hand, takes longer to respond than ordinary water. Because the O–D bond has a larger dissociation energy than the O–H bond, heavy water does have a lower reactivity than water.

• Deuterolysis occurs when water hydrolyzes certain inorganic salts. When heavy water is employed, similar reactions are called salt Deuterolysis.

AlCl₃+3D₂O→Al(OD)₃+3DCl

• Deuterium is released when heavy water combines with reactive metals like sodium and calcium, resulting in heavy alkalis.

2Na+2D₂O → 2NaOD+D₂

• When basic oxides like sodium monoxide and calcium oxide react with heavy water, they generate heavy alkalis.

Na₂O+D₂O → 2NaOD

• When heavy water combines with a variety of compounds containing liable hydrogen atoms, deuterium replaces H atoms partially or completely. The exchange mechanisms are more likely to occur when the compounds contain ionic (polar) hydrogen atoms.

NaOH+D₂O→NaOD+HDO

Uses of Heavy water

• Heavy water is used as a germicide and bactericide.
• The structure and basicity of many oxyacids were investigated using heavy water’s exchange reaction characteristic.
• Deuterium is produced from heavy water via electrolysis or a contact with an active metal such as sodium.
• In nuclear reactors, heavy water is used as a moderator. Slow neutrons are required for the fission of uranium atoms. By passing through heavy water, which acts as a moderator, the neutrons are delayed.
• In the study of aromatic electrophilic substitution reactions, metabolic activities, and other processes, heavy water is widely used as a tracer.

Conclusion

When two hydrogen atoms in regular water are replaced by deuterium atoms, heavy water is formed. D2O stands for deuterium oxide, which is a chemically heavy water. The discovery of heavy water is credited to Urey. One part of heavy water is found in every 6000 parts of ordinary water.