Ok so I am still having an issue with my calculator. I have 2 grams of H4EDTA, which has a molar mass of 292.24, this gives me 0.00684369 moles and there is 1 L of water, so this gives me a molarity of 0.00684369 moles per L. No issue there.
The pKa1 value is 2.07 which gives me a Ka1 value of .008511, pKa2 of 2.75 gives me .001778, pKa3 of 6.24 gives me .000000575439, and pKa4 of 10.34 gives me 0.00000000004571, Again no problem there.
The problem I am having is in M3-Q4, when take the kA1 value and mutiply it by the moles, I get 0.0085113804 * 0.006844 =0.000058249249809 then when I square it I get an H+ concentration of 0.0076321196.
In O4 if i just use the same 0.0076321196 then run it through the quadriatic formula i get an num error, if i use a negative of 0.0076321196 I get 0.0832099060
Both values of 0.0076321196 or 0.0832099060 are WAY too high, as the final value should be at .005642
When I try use only the 0.0085113804 * 0.006844 =0.000058249249809 without squaring it, and then make it negative, I am getting final value of .004488, which is lower than the required .00564. so what am I doing wrong did i make a mistake in the formula I wrote, do I have something in the wrong spot or is the formula that I am attempting to use incorrectly formed?
What I am trying to do is a chemistry problem, I am attempting to get an accurate H+ concentration of 2 grams of H4EDTA in 1 L of water so that I can calculate the correct pH.
Did I miss something???
Please let me know.
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