Steve_hi
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Magnesium nitrate
Today I bought 25kg of magnesium nitrate as 11-0-0 +16MgO fertilizer
can this be used to mix with NaCO3 PH- swimming pool product to make NaNO3
Magnesium nitrate and sodium carbonate react to form magnesium carbonate and sodium nitrate, according to Mt. Hood Community College. Both compounds
are ionic, meaning that part of each compound carries a positive or negative charge. In magnesium nitrate, the magnesium ion has a positive charge,
while in sodium carbonate, the carbonate group has a negative charge. The reaction occurs because the positively charged magnesium and negatively
charged carbonate are attracted to one another due to their ions. They bond, becoming neutral, while the already neutral nitrate and sodium combine
with one another.
Read more: http://www.livestrong.com/article/281620-magnesium-nitrate-s...
[Edited on 11-10-2011 by Steve_hi]
[Edited on 11-10-2011 by Steve_hi]
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Luftwaffe
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I believe this reaction is a metathesis reaction where you take advantage in differences in solubility. I found that the solubility of magnesium
carbonate is 0.101g per 100mL of water at 25C whilst sodium nitrate has a solubility of 92.1g per 100mL at 25C. When you mix magnesium nitrate and
sodium carbonate, magnesium carbonate will precipitate out as it's almost insoluble in water leaving only sodium nitrate and small amounts of
impurities in the fertilizer. Just filter and evaporate for your sodium nitrate.
I also took into account the solubility of magnesium nitrate and sodium carbonate to find them pretty soluble in water so they would not
precipitate before magnesium carbonate.
In general that write-up seems very primitive as of course all ions have charges. and sodium and carbonate are certainly not neutral or else they
wouldn't combine with each-other!
Edit: changed solubility data for sodium nitrate
[Edited on 12-10-2011 by Luftwaffe]
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barley81
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Check again - there is NO WAY that the solubility of sodium nitrate is 921 grams per 100 mL at 25C. Wikipedia says it is 921g / L
[Edited on 12-10-2011 by barley81]
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ScienceSquirrel
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You are better off using the solubility table here http://en.wikipedia.org/wiki/Solubility_table when trying to prepare simple salts. You would also be better off using potassium carbonate as
potassium nitrate crystallises easily due to the steep solubility curve and it is not hygroscopic when pure.
http://www.livestrong.com/article/281620-magnesium-nitrate-s...
To be honest some of that article is rubbish. The MSDS was written by someone who seems to have no knowledge of chemistry at all. Magnesium carbonate
in particular is completely innocuous and magenesium and sodium nitrate do not ignite on exposure to air.
[Edited on 12-10-2011 by ScienceSquirrel]
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Steve_hi
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Thanks science squirrel but I have easy access to NaCO3 and cheaply as ph- at the local hardware store $4.13 for 2 kilograms and no access to KCO3
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Retard-3000
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You can always use a different potassium compound in place of potassium carbonate so long as the anion it's bonded to will form an insoluble salt with
magnesium. One example would be potassium hydroxide.
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