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Author Topic: Shelf life of Water  (Read 8541 times)

Offline Nanac

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Shelf life of Water
« on: 17/09/2006 20:07:23 »
Hi, What would be the shelf life of Intact Pure water (like Injectable water ) and what would be the degraded product of water molecule after shelf life ?


 

another_someone

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Re: Shelf life of Water
« Reply #1 on: 17/09/2006 22:10:04 »
Water has existed on this planet for billions of years without any depreciable degradation.  In the long run, water exposed to ionising radiation (as to some extent we all are) will decompose to hydrogen and oxygen, but the amount of radiation we are exposed to on the surface of the Earth is sufficiently slight, that the rate of decomposition would be negligible.

Of greater concern might be the degradation of the container in which the water is stored.



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Offline lightarrow

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Re: Shelf life of Water
« Reply #2 on: 18/09/2006 14:07:06 »
quote:
Originally posted by Nanac

Hi, What would be the shelf life of Intact Pure water (like Injectable water ) and what would be the degraded product of water molecule after shelf life ?

Proton's half life ~ 10^36 years according to Wikipedia: http://en.wikipedia.org/wiki/Proton_decay
quote:
Despite the lack of observational evidence for proton decay, some grand unification theories require it. According to some such theories, the proton would have a half-life of 10^36 years, and would decay into a positron and a neutral pion that itself immediately decays into photons in the range of gamma radiation.
So, according to those theories, proton would decay into photons and antielectrons, but these last would annichilate with the atom's electrons, so at the and your water would become...light and nothing else. But you should wait much more than the present age of the universe.

Injectable water, however, is not pure, not only because it's a 0.9% solution of NaCl, but because it cannot be infinitely pure, so it may contain a very little amount of impurities, like organic compounds together with some microorganism cells; so, maybe, it cannot be guaranteed as injectable for many years.
« Last Edit: 19/09/2006 12:26:41 by lightarrow »
 

another_someone

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Re: Shelf life of Water
« Reply #3 on: 17/09/2006 22:10:04 »
Water has existed on this planet for billions of years without any depreciable degradation.  In the long run, water exposed to ionising radiation (as to some extent we all are) will decompose to hydrogen and oxygen, but the amount of radiation we are exposed to on the surface of the Earth is sufficiently slight, that the rate of decomposition would be negligible.

Of greater concern might be the degradation of the container in which the water is stored.



George
 

Offline lightarrow

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Re: Shelf life of Water
« Reply #4 on: 18/09/2006 14:07:06 »
quote:
Originally posted by Nanac

Hi, What would be the shelf life of Intact Pure water (like Injectable water ) and what would be the degraded product of water molecule after shelf life ?

Proton's half life ~ 10^36 years according to Wikipedia: http://en.wikipedia.org/wiki/Proton_decay
quote:
Despite the lack of observational evidence for proton decay, some grand unification theories require it. According to some such theories, the proton would have a half-life of 10^36 years, and would decay into a positron and a neutral pion that itself immediately decays into photons in the range of gamma radiation.
So, according to those theories, proton would decay into photons and antielectrons, but these last would annichilate with the atom's electrons, so at the and your water would become...light and nothing else. But you should wait much more than the present age of the universe.

Injectable water, however, is not pure, not only because it's a 0.9% solution of NaCl, but because it cannot be infinitely pure, so it may contain a very little amount of impurities, like organic compounds together with some microorganism cells; so, maybe, it cannot be guaranteed as injectable for many years.
« Last Edit: 19/09/2006 12:26:41 by lightarrow »
 

Offline daveshorts

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Re: Shelf life of Water
« Reply #5 on: 18/09/2006 20:15:54 »
Yes the think that would limit the shelf life would be it becoming non-sterile, or the container leaking some sort of chemical into it. The shelf life of tap water is a few days, filtered water considerably less than this, I have no idea how long the injectable saline would last though
 

Offline daveshorts

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Re: Shelf life of Water
« Reply #6 on: 18/09/2006 20:15:54 »
Yes the think that would limit the shelf life would be it becoming non-sterile, or the container leaking some sort of chemical into it. The shelf life of tap water is a few days, filtered water considerably less than this, I have no idea how long the injectable saline would last though
 

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Re: Shelf life of Water
« Reply #6 on: 18/09/2006 20:15:54 »

 

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