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If 1,2,3,4 moles of H3PO4, NaH2PO4, Na2HPO4, and Na3PO4 are mixed in an aqueous solution.find the pH. given for H3PO4,

Ka1=10^(-3), Ka2=10^(-7), ka3= 10^(-13)


The ph value is less than 9 and greater than 5 

it is in my book page no 47

please mark it as best please !

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It depends on the concentration. pH is the negative log of the concentration of H+ atoms in a solution (measured it molarity, mol/L). Phosphoric acid (H3PO4) has 3 Hs in it, so for every molecule of acid dissolved, there are 3H+ ions.

But Phosphoric acid isn't a strong acid, so it doesn't completely dissolve in water. You can tell whether an acid is strong or not by looking at the number of Os and Hs. If it has 2 more Os than Hs, it is strong.

One must look up how thoroughly the acid dissolves in water. By looking it up on wolframalpha, I find that for every mole of H3PO4
In the solution, 1.06 moles of H+ are present. So if I take the -log1.06, I find the pH of 1M phosphoric acid, which is 1.1.
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