Textbook Question
Use the appropriate values of Ksp and Kf to find the equilibrium constant for the reaction. PbCl2(s) + 3 OH-(aq) ⇌ Pb(OH)3-(aq) + 2 Cl-(aq)
Ch.17 - Aqueous Ionic Equilibrium
Chapter 17, Problem 115
A buffer is created by combining 150.0 mL of 0.25 M HCHO2 with 75.0 mL of 0.20 M NaOH. Determine the pH of the buffer.
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<Calculate the moles of HCHO2 by multiplying its concentration (0.25 M) by its volume (0.150 L).>
<Calculate the moles of NaOH by multiplying its concentration (0.20 M) by its volume (0.075 L).>
<Determine the moles of HCHO2 that react with NaOH, noting that NaOH is a strong base and will react completely with HCHO2.>
<Calculate the moles of the conjugate base (CHO2-) formed from the reaction of HCHO2 with NaOH.>
<Use the Henderson-Hasselbalch equation, \( \text{pH} = \text{pK}_a + \log \left( \frac{[\text{A}^-]}{[\text{HA}]} \right) \), to find the pH of the buffer, where \([\text{A}^-]\) is the concentration of the conjugate base and \([\text{HA}]\) is the concentration of the remaining acid.>
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