Ask A Scientist© Chemistry Archive

 >>
 >>    name         Lisa Rodgers
 >>    status       student
 >>    age          17

 >>    Question -   I am conducting a science experiment for our science 
fair at
 >>Resurrection High School to find out the difference between
 >>inorganic versus organic fertilizer.  Would it be possible for you
 >>to provide me with the molecular formula for the following types of
 >>fertilizer?  I am trying to figure out the molarity for each
 >>fertilizer. To help, I have provided the ingredients of each:
 >>
 >>Miracle-Grow Plant food for houseplants 15-30-15
 >>
 >>Total Nitrogen (N) 15%
 >>5.8% Ammoniacal Nitrogen
 >>9.2% Urea Nitrogen
 >>Avaiable Phosphate(P2O5)  30%
 >>Boron (B)                 0.02%
 >>Copper (Cu)(Soluble)      0.07%
 >>Iron (Fe)                 0.15%
 >>0.15% Chelated Iron
 >>Manganese (Mn)            0.05%
 >>0.05%  Chelated Manganses
 >>Molybdenum (Mo)           0.0005%
 >>Zinc (Zn) (Soluble)       0.6%
 >>
 >>Milorganite
 >>
 >>Nitrogen (N)    6.75%
 >>Phosphorus (P)  2.65 %
 >>Potassium (K)   0.46%
 >>Calcium (Ca)    0.98%
 >>Sulfur (S)      0.71%
 >>Magnesium (Mg)  0.50%
 >>Iron (Fe)       5.30%
 >>Zinc (Zn)       0.05%
 >>Copper (Cu)     0.03%
 >>Manganese (Mn)  0.03%
 >>Boron (B)       Trace
 >>Chlorine (Cl)   Trace
 >>Molybdenum (Mo) Trace
 >>
 >>10-10-10 lawn fertilizer
 >>
 >>Total Nitorgen (N)    10%
 >>3.92% Ammoniacal Nitrogen
 >>6.08% Urea Nitrogen
 >>Phosphate P2O5        10%
 >>Soluble poash   K2O   10%
 >>Derived fron Urea NH3 Phosphate and muriate of potash
 >>
 >>Schultz Plant Food 10-15-10
 >>
 >>Total Nitrogen (N)          10%
 >>1.6% Ammoniacal Nitrogen
 >>0.2% Nitrate Nitorgen
 >>8.2% Urea Nitrogen
 >>Available Phosphate (P2O5)  15%
 >>Soluble Potash (K2O)        10%
 >>Iron (Fe)    0.10%
 >>0.10% Chelated Iron (Fe)
 >>Manganese (Mn)              0.05%
 >>0.05% Chelated Manganese (Mn)
 >>Zinc (Zn)                   0.05%
 >>0.05% Chelated Zinc (Zn)

I don't know all the information you are looking for, but I can give you a
start.  Urea is a compound of carbon, oxygen, nitrogen, and hydrogen, of
the formula (NH2)2C=O.  When the contents specify "ammoniacal nitrogen," it
means some ammonium (NH4+) salt.  This salt is probably tribasic ammonium
phosphate (NH4)3PO4, dibasic ammonium phosphate (NH4)2HPO4, or monobasic
ammonium phosphate (NH4)H2PO4.  I don't know what form your boron, copper,
iron, zinc, etc. are in.  "Muriate of potash" is just another name for
potassium chloride, KCl.  "Nitrate nitrogen" is usually in the form of
ammonium nitrate NH4NO3, or potassium nitrate, KNO3.

Richard Barrans
Chemical Separations Group
Argonne National Laboratory

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