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You may find the Henderson-Hasselbalch equation useful when using buffers [conjugate base] pH = pk + log10 [acid] (a) A buffer solution (Buffer 1) contains 0.170 mol L-1 malonic acid, HOOC(CH₂)COOH, and 0.0850 mol L-1 sodium hydrogen malonate, which contains the conjugate base, HOOC(CH₂)COO™. Calculate the pH of this buffer, given the pKa for malonic acid is 2.85 and that a equal volume of each solutions is used. Show all working. (b) A second buffer solution (Buffer 2) contains 0.0850 mol L-1 malonic acid, HOOC(CH₂)COOH, and 0.0425 mol L-1 sodium hydrogen malonate, which contains the conjugate base, HOOC(CH₂)COO™. Which buffer solution (Buffer 1 or Buffer 2) would have the higher buffer capacity? Explain your answer. (c) A small amount of a strong acid (HCI) is added to the solution in part (a). Explain, with the aid of a balanced chemical equation, why the pH of the buffer does not change as a result of the addition of the acid. In your answer, identify which component of the buffer - the acid (HOOC(CH₂)COOH) or the conjugate base (HOOC(CH₂)COO™) - would react with the HCI.