Question

2555 Consider the solution formed when 500 ang but CH,COOH, a bad-smelling organic acid (formed when butter turns rancid), is dissolved in water to make 100 ml. of solution. The pH of the solution is 2.52. Calculate K and pK, for butyric acid. 15.56 When 1.00 g thiamine hydrochloride (also called vita- min B, hydrochloride) is dissolved in water and then diluted to exactly 10.00 mL, the pH of the resulting solu tion is 4.50. The formula weight of thiamine hydrochlo- ride is 337.28. Calculate K, and pK, for this acid. 1537 If a 0.0100 M solution of caproic acid, thought to be at least partially responsible for the unique and generally considered foul) smell of goats, has a pH of 3.43, what is K, and pK, Lactic acid, CH,CH(OH)COOH, forms in muscles as a by product of their contraction. If the pH of 0.0376 M solution is 2.66, what is K, and pk, for lactic acid

Answer 1

Caproic Acid DIssociation ka = Given: pH 3.43 eaproic acid] = o0 100 M [40J-1 Noww LHg0J= becoanse ohen x moles eaproic acid dissociates n moles to ive moles o H2or amd PHLog C 3 43 0=10 -pH - 3 43 =1D ka iO 343 X D3 43 1.38 x105 00100 X pka =-log ka-Log3816) AT14 4 = 4.86