A buffer solution is prepared by mixing 500.0 mL of 0.600 M CH3COOH with 500.0 m
ID: 487858 • Letter: A
Question
A buffer solution is prepared by mixing 500.0 mL of 0.600 M CH3COOH with 500.0 mL of a 1.00 M CH3COONa solution. What is the pH of the resulting solution?
Calculate the cell emf for the following reaction: 2Ag+ (0.10 M) + H2 (1.0 atm) Æ 2Ag(s) + 2H+ (pH = 8.00)
Methyl orange is an indicator (buffer solution) that is red in its acidic form (HMO) and orange in its basic form (MO- ). A solution at pH 5.0 contains methyl orange. Calculate the ratio of concentrations [MO- ]/[HMO] in this solution. pKa methyl orange = 3.9
Explanation / Answer
no of moles of CH3COOH = molarity * volume in L
= 0.6*0.5 = 0.3 moles
no of moles of CH3COONa = molarity * volume in L
= 1*0.5 = 0.5 moles
PH = PKa + log[CH3COONa]/[CH3COOH]
= 4.75 + log0.5/0.3
= 4.75 + 0.2218 = 4.9718
H2 ----------------> 2H+ + 2e- E0 = 0.00V
2Ag+ + 2e- ------> 2Ag E0 = 0.8V
----------------------------------------------------
2Ag+ + H2------> 2Ag(s) + 2H+ E0 cell = 0.8V
Ecell = E0cell- 0.0592/n logQ
= 0.8 -0.0592/2 log[H+]2/[Ag+]2 PH2
= 0.8 -0.0296log(10-8)2/(0.1)2 *1
= 0.8-0.0296*-14 = 1.2144V
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.