Question

Remember that only the answer with three decimal places. D Question 27 1 pts Calculate the pH of a 0.145 M KCIO solution. Remember that only the decimal places in a pH represent significant figures. Please enter your answer with three decimal places.

Answer 1

27. Crive data in concentration of kao – 0.115 M We have to calculate the pH of this solution. Kalo in a salt which is produced by the renn of weak acid Hao and strong borse KOH kalo undergoes hydrolysis in the following way- ² Hoce KOH Initial Egm. 0. 145(1-2) 0.1452 kalo & H₂O 0.145M 0 O 0.145 x Hydrolysis conat. (ka) degree of where, a= hydrolysis be [HOUJ ĽKOH] IKO [HOUJ x [H307] x [KOH] [ko] [H2,017 30 we write it as - (1) ¢ 1 CHO 1 LO 1] ки Icio"] [40] KW ka نادا where, Kw = ionic product of watey - THU 3 Tổ HOCO + H₂O & H₂Ot & clo And for Hoch,

ka - Dissociation const. of acid (here it HOU) [H3O+] [ con [H0c] Again from the above hydrolysis rean, ren, we can write Kn 0.1458 x 0. 145 x 0.145(1-2) O. 145 x x 1 1- x ~ O. 145x2 (11 [x is verey small so 1x ni we get - from equation & (ug 0.145 x² KW ka Kw a, x Kax 0.145

from the hydrolysis egun we get. С кон] i. е. Ібн J. o. 145 х. = 0. 14ѕ ko Кахб. 14S К ХО, 145 ка БОН — 17 L бу] log У. ко (%, хол с ) - wo kw - 2 lag 8.145 te lig ka 1/2 pk w Арка - по 145 1) -трон БК — БОН Again, we know that, он Бkw pH на F*, *р* *} +7 o-145 4 + 2 S = ac-145) Ко 8% HOct upka = -log ka - - (2-8 яг“) 2. 8 xo 8 10. 256 - 1, 55 1. рН 4 0.145 Мки0 s sluulim » 10. 256 .