Heavy water

the properties, production, application, effects on animals and plants

1. NAME MATRIC NO. AZLINI BINTI RAZALI 169980 KHAIRAIN MARSELA BINTI IDRUS 169102 NUR SYAFIQAH BT. CHE OMAR 170173 MADIHAH ALI 170286

2. Heavy water is water that contains heavy hydrogen or deuterium. Deuterium differs from the hydrogen usually found in water, protium , in that each atom of deuterium contains a proton and a neutron Heavy water may be deuterium oxide, D2O or it may be deuterium protium oxide, DHO. Definition Molecule Ordinary water

3. Heavy water is 10.6% denser than ordinary water I t melts at 3.7 °C, and thus endures very well in ice-cold normal water D2O becomes concentrated in the liquid residue because it is less volatile than H2O Chemical Properties Physical Properties

4. Azlini bt razali 169980 Production of heavy water & sources of heavy water

5. Heavy water occurs naturally, although it is much less common than regular water. Approximately one water molecule per twenty million water molecules are heavy water.

6. Possible methods for producing heavy water on an industrial scale: 1) water- hydrogen sulphide exchange process (GS process) 2) ammonia- hydrogen exchange process.

7. The  Girdler sulfide (GS) process , also known as the  Geib–Spevack (GS) process , is a method for filtering out of natural water the heavy water(deuterium oxide = D 2 O) in nuclear reactors (as a coolant and moderator)

8. Consists of two sieve tray columns. One column is maintained at 30 °C and is called the cold tower and the other at 130 °C and is called the hot tower. The enrichment process is based on the difference in separation between 30 °C and 130 °C. Water flows down the towers while the hydrogen sulphide gas circulates from the bottom to the top of the towers. The product of the last stage, water enriched up to 30% in deuterium, is sent to a distillation unit to produce reactor grade heavy water (ex: 99.75% deuterium oxide)

9. have adverse health effects and mice given 80% heavy water died within days . replacing hydrogen with its heavier isotope deuterium slows down the rate of any chemical reaction. The major reason for the difference in the rates of the chemical reactions involving the two isotopes of hydrogen is the difference in their masses. Effect on biological systems (Animal)

10. bean plants grown from seed given increasing fractions of heavy water showed stunted growth compared with control plants given normal water. chemical reactions of heavy water are slower than those of ordinary water. (Plant)

11. Application tracer in clinical nutrition determining normal parameters of human physiology, among infants, pregnant and lactating mothers enhance the thermostability of certain vaccines improved intensity and better transmission characteristics of deuterated PMMA (Poly methyl meta acrylate ) Drug development and therapy

12. REFERENCES Dr. P. S. Chauhan (2015 ). Heavy Water: Alternative applications in biology, medicine and industry. India: Department of Atomic Energy. Per F Dahl (1999). Heavy Water and the Wartime Race for Nuclear Energy. Britain : IOP Publishing LTD