A mixture of 0.060 moles HEPES (a weak acid) and 0.040 moles of its sodium salt (Na+HEPES-) are dissolved in 1.00 L water. The pKa of HEPES is 7.55.
what is the pH?
what is the pH?
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pH = pKa + log[salt/weak acid]
0.06 mols HEPES / 1 L water = 0.06 M weak acid
0.040 mols of sodium salt / 1 L = 0.04 M Salt
pH = 7.55 + log[0.04 / 0.06]
pH = 7.37
0.06 mols HEPES / 1 L water = 0.06 M weak acid
0.040 mols of sodium salt / 1 L = 0.04 M Salt
pH = 7.55 + log[0.04 / 0.06]
pH = 7.37