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g Devon’s laboratory is out of material to make phosphate buffer. He is considering using sulfate to make a buffer instead. The pKapKa values for the two hydrogens in H2SO4H2SO4 are −10−10 and 2.2. Will this approach work for making a buffer effective near a pH of 7?7?

User Elfling
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1 Answer

4 votes

Answer:

Due to operator log it is impossible to reach a pH of 7 with these pKa's or acids used.

Step-by-step explanation:

Since the pKa values provided are not near to 7, reaching a neutral pH is not possible because of the governing equation equation of Buffer:


pH = pKa + log (HA)/(A^(-) )


pH - pKa = log (HA)/(A)\\7-2.2 = log x \\4.8 = log x \\10 ^(4.8) = x\\ x = 63 095\\

where x is\frac{HA}{A}

So the ratio of HA and A is vastly big so then it is almost impossible to arrive to this number.

User David Kay
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