The approximate difference in the concentration of hydrogen ions between the two solutions is 8.7.
pH is the measure of how acidic and basic a liquid is. The full form of pH is potential hydrogen.
By the formula of pH
pH = -log [H +]
[tex][H^+] = 2 \times 10 ^ -^9[/tex]
[tex]pH = -log (2 \times10 ^ -^9)[/tex]
pH = 8.7
Thus, the pH difference is 8.7.
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