Question

A 1.00-litre buffer solution is made up containing 0.100 mol acetic acid and 0.200 mol sodium acetate: what is its’ pH? Then, 0.0500 mol of HCl gas is bubbled into the solution (assume no change in volume): what is the new pH? Data: pKa for acetic acid = 4.76

Answer 1

Date DELTA PONO. DA up of + Gren ther Buffer is Acidic buffer which is made weak and caracoons & Salt of weak acid y strony dase (CH3COONal. Ne, the pH of the suffer solution is grien by- pH phat togio & salt (Ald] Liven Data No. of moles of CH₃COOH 0.100 moles CH3COONa = 0.200 moles Nolume 1 lt. pka = 4.76. pH = 10.2007 [0.100/13 pH = [109 - 0:30] pH? _4.76 + 0.30 11 1 11 2 4.76 + logio 4.76 + logio 2 PH₂5.00 if we add 0.0500 moles of Hill, then we have three Кршій іс. НscopH CHOCOONa 4 Hll. so, Hll will Tract with CHiCoona only only. CHCOONa + He CH₃COOH + Nall. Ewittely 0.200motes Duosoombles O'too moles Usef moles. 0.0500. 0.0500 00500 0.1500 moles X 0.1500 miles formed. 2 Remaining te. 0.0500 moles of Hill react with 0.0500 moles of CHICOONa to form 0.0500 moles of Chi con. so finally with 0.1500 moles of Chaoona & CHLOH= 0.1500 moles formed. left pH prat los I salt! [ And PH 4.76+ lo io [0.13.00/, ] PO 150011] 4.76 + 10/10 (1) 4.76to 2 4.76 so the ми рн в 4:6. 2 [PH