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Chemistry 101
Having commented earlier on Steve's chemistry problems, I got to
thinking about some of my own blunders that may help others. It
mainly deals with the solubilities of the common macro chemicals
we use with our plants. I remember weighing out a good amount of
K2SO4 and trying to dissolve it in 100ml of water and had a time
with it not dissolving, eventually dumping it out and starting over.
This is not a good thing, since we only get limited amounts of
chemicals and wasting them is not an option. I looked up the sol.
constants for my chemicals and everything works great now. I
thought I'd pass it on. Remember, the number of grams is the
theoretical limit and it's always good to back down a few grams to
make sure everything does dissolve, or even to a whole number,
which makes calculating a lot easier. All solubilities are @ 25C.
CaCL2 - freely sol in water, very exothermic.(I use a 50% solution).
MgCl2 - freely sol in water, exothermic, pH~7.(I use 30%)
KCl - 35.7g/100ml water pH~7.
CaCO3 - practically insol in water, sol in dilute acids(Carbonated
water is acidic if the kH values are low, thus dissolving small
amounts of CaCO3).
KNO3 - 35.7g/100ml (same as KCl), endothermic rxn, pH = 7.
K2SO4 - 12.0g/100ml, pH = 7 (10g/100ml takes forever to dissolve,
so 12g/100ml would drive you mad, believe me!)
MgSO4 - (Epson salt) -sol in water @ 20C 71g/100ml, pH~6-7.
Jamie, enjoying the Indian Summer.