Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: paul.fr on 22/04/2008 23:39:09

Title: The drinking of and making ice cubes from heavy water.
Post by: paul.fr on 22/04/2008 23:39:09
What difference ,if any, would i notice if i made ice cubes out of heavy water as opposed to 'standard' water? could i drink the contents of the glass with heavy water ice cubes in it?
Title: The drinking of and making ice cubes from heavy water.
Post by: another_someone on 23/04/2008 02:08:09
Quote
Physical data
    Appearance: colourless liquid
    Melting point: 4 C
    Boiling point: 101.4 C
    Specific gravity: 1.107
    Vapour pressure: 16.4 mm Hg at 20C
    Flash point:
    Explosion limits:
    Autoignition temperature:
Toxicology
    Not hazardous according to Directive 67/548/EEC. High concentrations in the body can affect biochemical processes. Ingestion of large amounts impairs kidney function, CNS operation.


http://en.wikipedia.org/wiki/Deuterium#Physical_properties
Quote
The physical properties of deuterium compounds can be different from the hydrogen analogs; for example, D2O is more viscous than H2O. Deuterium behaves chemically similarly to ordinary hydrogen, but there are differences in bond energy and length for compounds of heavy hydrogen isotopes which are larger than the isotopic differences in any other element. Bonds involving deuterium and tritium are somewhat stronger than the corresponding bonds in light hydrogen, and these differences are enough to make significant changes in biological reactions (see heavy water).

Deuterium can replace the normal hydrogen in water molecules to form heavy water (D2O), which is about 10.6% more dense than normal water (enough that ice made from it sinks in ordinary water). Heavy water is slightly toxic in eukaryotic animals, with 25% substitution of the body water causing cell division problems and sterility, and 50% substitution causing death by cytotoxic syndrome (bone marrow failure and gastrointestinal lining failure). Prokaryotic organisms, however, can survive and grow in pure heavy water (though they grow more slowly). Consumption of heavy water would not pose a health threat to humans unless very large quantities (in excess of 10 liters) were consumed over many days. Small doses of heavy water (a few grams in humans, containing an amount of deuterium comparable to that normally present in the body) are routinely used as harmless metabolic tracers in humans and animals.
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Title: The drinking of and making ice cubes from heavy water.
Post by: Bored chemist on 23/04/2008 19:16:13
I'm not sure, but I think "heavy ice" would sink in ordinary water- even more likely to sink in alcoholic drinks.
Title: The drinking of and making ice cubes from heavy water.
Post by: another_someone on 23/04/2008 21:12:35
Quote from: Bored chemist on 23/04/2008 19:16:13
I'm not sure, but I think "heavy ice" would sink in ordinary water- even more likely to sink in alcoholic drinks.

Yes, the numbers above (as well as seeing it explicitly stated elsewhere) make heavy ice 10% heavier than light water.
Title: The drinking of and making ice cubes from heavy water.
Post by: syhprum on 23/04/2008 21:35:20
In the fourties heavy water was considered a very expensive strategic commodity, no doubt things have changed since then.
Is it easy to purchase it and what is the cost?.
Title: The drinking of and making ice cubes from heavy water.
Post by: rosalind dna on 24/04/2008 16:26:41
What is "heavy water"?
Title: The drinking of and making ice cubes from heavy water.
Post by: Soul Surfer on 25/04/2008 09:52:37
There are three isotopes of hydrogen one with no neutrons (normal hydrogen)  one with one neutron,  Duterium or "heavy" hydrogen, and one with two neutrons  tritium (this is radioactive)  all hydrogen contains a small amount of duterium.  This was formed during the big bang and at no other time.  heavy water is "water" formed out of duterium and oxygen
Title: The drinking of and making ice cubes from heavy water.
Post by: syhprum on 25/04/2008 11:55:39
I believe you meant "with three nucleons", one Proton and two Neutrons