Question

Question 2 A clarified wastewater containing 5 mg/L NH3-N is to be breakpoint chlorinated. The water has an alkalinity of 100 mg/L as CaCOs. Determine i. The stoichiometric requirement for Cl2. ii. If the water is sufficiently buffered. The increase in dissolved solids to be expect. [15 marks) Question3 The pH of a 0.1 Msolution of sodium bicarbonate is adjusted to 7.0 with a strong acid. A 100 mL portion of this solution is obtained, and to this volume 100 mL of 0.08 N HCI is added. What are the final H2CO and HCO5 concentrations and resulting pH?

Answer 1

Daios-4) cd ANSWER: (Question -2) Celarijied) where it s to be Gven waste water break point ch lorinated Containins 5mgl N H3-N <f+ F toongl as Ca (02 Alkalinit o wa ter Now i Here, 2 units of Nt require lunit og cl place Ha ke reaction dor the 5 mg IL ot NHs requires -Euot Po 1Aus th reattion to talke place toi renot Suiciently 41 Yes.we lan sa that water i as the Allkalinit o water is guite bured ie. loomg/L. 6ESH low Page-

Question-3 a oIM Solurtion of Ma (o, is 4.0 Given PH ot N HL Isadded to this volume 100 mL ot 0'os Now we have pH=PKalt LogliHcos/(HzLo i-e. 76:37 +Log Llo1-Hos)) 1u12c0s Log [co1-(t (os) o dof -6.32 o.63 o63 al- 4.26 arHo -0) .e D.O19M H CO3 O 1- O o01 -o.osiM, Final HLo) = (100x o.0194100 x0 o g)m mot l00 tH00)m 0'0495M. os)nmolo0t lo0)m) Final [Hco] (100 x0 '081-100 AD a 2 0005M diniley PH 637 +Lo (o 00 05/0.0 u95) Reating