Problem: What concentrations of acetic acid (pKa = 4.76) and acetate would be required to prepare a 0.20 M buffer solution at pH 4.5? Enter your answer to two significant figures. (For example, 0.0090 and 0.0097 each have two significant figures, whereas 0.009 has only one significant figure.)

FREE Expert Solution

Step 1

pH = pKa + log(conjugate baseweak acid )log(conjugate baseweak acid ) = pH - pKa log(conjugate baseweak acid ) =4.5 - 4.76log(conjugate baseweak acid ) log=-0.26log(conjugate baseweak acid ) =10-0.26(conjugate baseweak acid )  = 0.5495


Step 2

conjugate base = 0.54950.5495+1.00 = 0.3546

weak acid = 1.000.5495+1.00 = 0.6454


Step 3

For 1 L of 0.20 M buffer solution,


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Problem Details

What concentrations of acetic acid (pKa = 4.76) and acetate would be required to prepare a 0.20 M buffer solution at pH 4.5? Enter your answer to two significant figures. (For example, 0.0090 and 0.0097 each have two significant figures, whereas 0.009 has only one significant figure.)

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