HydroRocks
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Here is a GREAT source of information for those of you trying to understand and better your knowledge, especially if your running hydroponics.........as science of today advances, we are finding that we basically know sqwat about water, and yet it is just assumed that we understand what it even IS!
C&P Snipet From site:
The Science
What is "ionized water"?
To a chemist like myself, the term is meaningless. True, it is possible for water to contain dissolved ions (electrically-charged atoms or molecules), but that's something else again. Almost all waters found in nature acquire ions such as calcium and bicarbonate as they come into contact with rocks and sediments. Even the purest rainwater contains some hydrogen- and bicarbonate ions that are formed when it picks up carbon dioxide in the atmosphere.
Pure water consists almost entirely of H2O molecules loosely bound in a network-like structure in which individual molecules are constantly changing partners. Water molecules exhibit a very slight tendency to dissociate ("ionize") into hydrogen ions and hydroxide ions:
H2O → H+ + OH–
but the extent of this reaction is severely limited by the fact that the reverse of this reaction is much more rapid, so that on the average, only about two out of every billion H2O molecules are dissociated. No electrical device or chemical additive is capable of increasing these ion concentrations in pure water above this very minute level which is so small that for most practical purposes pure water can be considered to be ion-free, as evidenced by the fact that it will not conduct an electric current.
Pure water cannot undergo significant electrolysis
One more thing about the electrolysis of water having very low ion content: because of the very small number of ions in such water, it conducts electric current very poorly, so the process is extremely slow and inefficient. This means that if your water supply is free of dissolved minerals, no significant amount of electrolysis will occur.
For electrolysis to occur to any practical extent, additional ions must be present in order to transport the current. For example, the large-scale electrolysis of water to manufacture highly pure H2 and O2 is carried out by adding sulfuric acid. The sulfate ions help carry the current, but they do not react at the positive electrode because H2O is more easily decomposed.
... so if your water comes from a well and contains dissolved salts or "hardness ions" such as calcium or magnesium in medium concentrations, electrolysis might be possible, but it will not be effective in removing impurities. It should be noted that groundwaters are usually somewhat alkaline to start with.
Many "water ionizer" devices depend on the addition of ordinary salt to make the water more conductive. Electrolysis of a dilute sodium chloride solution liberates hydrogen gas and hydroxide ions at the cathode, producing an alkaline solution that consists essentially of sodium hydroxide NaOH which can be drawn off as “alkaline water”. At the anode, chloride ions are oxidized to elemental chlorine. If some of this chlorine is allowed to combine with some of the hydroxide ions produced at the cathode, it disproportionates into hypochlorous acid HOCl, a weak acid and an oxidizing agent. Some ionizer devices allow the user to draw off this solution for use as a disinfecting agent. In many cases the two streams can be combined to form a mixture consisting of both HOCl and sodium hypochlorite (equivalent to diluted ordinary laundry bleach), depending on the pH desired.
So buying a "water ionizer" is a very expensive way of obtaining a solution that you could in principle make yourself by diluting some laundry bleach, and perhaps adjusting the pH by adding a weak acid such as lemon juice. But would you want to drink this "eau de Clorox"? Don't try this at home!
Full source found here:
http://www.chem1.com/CQ/ionbunk.html
C&P Snipet From site:
The Science
What is "ionized water"?
To a chemist like myself, the term is meaningless. True, it is possible for water to contain dissolved ions (electrically-charged atoms or molecules), but that's something else again. Almost all waters found in nature acquire ions such as calcium and bicarbonate as they come into contact with rocks and sediments. Even the purest rainwater contains some hydrogen- and bicarbonate ions that are formed when it picks up carbon dioxide in the atmosphere.
Pure water consists almost entirely of H2O molecules loosely bound in a network-like structure in which individual molecules are constantly changing partners. Water molecules exhibit a very slight tendency to dissociate ("ionize") into hydrogen ions and hydroxide ions:
H2O → H+ + OH–
but the extent of this reaction is severely limited by the fact that the reverse of this reaction is much more rapid, so that on the average, only about two out of every billion H2O molecules are dissociated. No electrical device or chemical additive is capable of increasing these ion concentrations in pure water above this very minute level which is so small that for most practical purposes pure water can be considered to be ion-free, as evidenced by the fact that it will not conduct an electric current.
Pure water cannot undergo significant electrolysis
One more thing about the electrolysis of water having very low ion content: because of the very small number of ions in such water, it conducts electric current very poorly, so the process is extremely slow and inefficient. This means that if your water supply is free of dissolved minerals, no significant amount of electrolysis will occur.
For electrolysis to occur to any practical extent, additional ions must be present in order to transport the current. For example, the large-scale electrolysis of water to manufacture highly pure H2 and O2 is carried out by adding sulfuric acid. The sulfate ions help carry the current, but they do not react at the positive electrode because H2O is more easily decomposed.
... so if your water comes from a well and contains dissolved salts or "hardness ions" such as calcium or magnesium in medium concentrations, electrolysis might be possible, but it will not be effective in removing impurities. It should be noted that groundwaters are usually somewhat alkaline to start with.
Many "water ionizer" devices depend on the addition of ordinary salt to make the water more conductive. Electrolysis of a dilute sodium chloride solution liberates hydrogen gas and hydroxide ions at the cathode, producing an alkaline solution that consists essentially of sodium hydroxide NaOH which can be drawn off as “alkaline water”. At the anode, chloride ions are oxidized to elemental chlorine. If some of this chlorine is allowed to combine with some of the hydroxide ions produced at the cathode, it disproportionates into hypochlorous acid HOCl, a weak acid and an oxidizing agent. Some ionizer devices allow the user to draw off this solution for use as a disinfecting agent. In many cases the two streams can be combined to form a mixture consisting of both HOCl and sodium hypochlorite (equivalent to diluted ordinary laundry bleach), depending on the pH desired.
Full source found here:
http://www.chem1.com/CQ/ionbunk.html
