Question

The amino acid glycine has pKa values of 2.4 and 9.8. A solution was made by dissolving 1.15 g of glycine sodium hydrate (shown below) in 100.00 mL of water. The molecular weight of the salt is 115 g/mol 5. Нас .Н20 Na+ H2N What is the pH of the salt solution? 20-mL aliquot of would result, making sure to label at least four sets of values on the graph. a ior itrated with 0.100 M b on curve that

Answer 1

D.Olnnal a) mules of alt disoolved molaul f nalt duisolvnd = 0.01 mef 0.IL Lata uit gycinate Then tialy anion (o)T гдuithium: (o4-) =149.8-4.2 a -4.2 -Сон] poH-ao- -jaj (0-00251)= 26; pH=4-poH=L4 ) 1 = (K-1.o) 2.10R5) M b) At irstivlsme point, Vu = 20m, glycine n Yast as BH Now aarophiotic (4 acid andl Las2). Bt Fr puh act bot can is given by pH pka, t pka = 2.4+9.8 pH Aubatance 2 6.1 pH at h (VLU here at pH- pka,9.8 - imi lanly par be Mideuay evueen dut and and uivoenu pka 2.4. mid nay a Jst Rguivaden Lat ivalinu poin/ At anduivalence point, gycine tuits as BHt VHL = 4omL, Yoteel 60mL O.1Mx 20mL hadfmay batmean Jaand2ndquvalince 2nd eivane Mgrt Folouu 9uili^vum dominates af 2nd. 24 Ruvalenco 6omL point point. 9 20 = quihum:

Comment if still any doubt.