The ph of the buffer solution given after 0.750 mol of H⁺ have been added is; 4.34
pKa = -log(Ka) = 4.20
[A⁻] = [NaC₇H₅O₂]
[HA] = [HC₇H₅O₂]
Concentration of NaC₇H₅O₂ in the preferred buffer solution is;
[132.8g/(144.11 g/mol * 300 mol)] * 1000 mL/1 L = 3.07 M
Formula for the PH here is;
pH = pKa + log [A⁻/HA]
Thus;
pH = -log(6.3 x 10⁻⁵) + log [3.07/2.31]
pH = 4.34
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