Question

Write out all relevant balanced chemical equations for each problem as we did in class. All chemical equations require balancing, correct charges, and phase designators. 15.00 mL of 0.350 hypochlorous acid is titrated with 0.175 M NaOH. Calculate the pH: 1) before adding any NaOH solution. 2) after adding 27.00 mL of the NaOH solution. 3) at the equivalence point.

Answer 1

Ho is a wealK aed and dissociats in aquious sokuto as HCo Caa) HCa) Coca9) Initial (M) change CM) Fqulibrium (M) - Coc Ca Coc Coc C- Initial Cone ef HClo and o digree of dissoctalton] Ка - Coc Ca LHCO LHt]= Coc = /Kare H-0g Ka of Hclo= 2.9x10 Доg кахс) Ing2.9xi35) 4.0 CAns 350 (M) 5 ml of 0.350 (M) HCLO 2. 15 xO.350 milimo Hclo 5.25 27xo.175 nilimole NaoH 27 ml o. I75(M) NaDH = 4.725 H C20 (ag)NaoH(ag)-Na cloCaa)H20) 4.725 milimole NaoH (aa) will neutralse 4 725milimde Hoca) and produee 4.725 milimole Nacuo cag) salt. Remaining Helo(ag in the sclutio =(525-4-725 0:525 Now the soludtion is a buffer of weakaud (HClo) anD ts salt with Shreng base (Nacio) ри рХа (нао) -+ вод =-log(29xi) log 54+0.95) milimoie [Naco] 4.25 3.49 Ans)

At eauivalente point all the Ho aud willreact to NaDH to tor Na elo an H20 of weak aud ana strong base will emdrgo salES Pydro- The pH oftha Solutton Can bl en as Naco being a salt par's pH7+pkalogENacio At eaivalence point VHCO MHoNaoHx MNao VHCOXM VNaoH M NaoH 73.770 06 ! 5 X O. 35O 660)30 Total volume f solution 10 83 CANS) (B +30)45 mL No. moes of Na cloxio Volumu of Solution 5.25X10X100M [Nauo! 45 DKa of Huo 754