Question

1. What is the voltage for: Cu2+ + Zn(s) → Cu(s) + Zn2+ at 298 K if [Cu2+] = 0.15 M and [Zn2+] = 4.0 M? E°cell = 1.20 V.



2. A 25.0 mL of aliquot of a well-shaken and filtered sample of river water is pipetted into an evaporating dish. The sample was heated to dryness. Determine the TDS content, express (a) in ppt and; (b) ppm using the

following data:

• Mass of evaporating dish = 24.44 g

• Mass of water sample + evaporating dish = 49.44g

• Mass of dried sample + evaporating dish = 25.37 g



3. A 25.0 mL of aliquot of a well-shaken of river water is pipetted into an evaporating dish. The sample was heated to dryness. Determine (a) TS and (b) TSS and express in terms of ppm using the following data:

• Mass of evaporating dish = 25.25 g

• Mass of dried sample + evaporating dish = 28.14 g



4. Solve the missing data:

Sample volume (mL) = 250

Buret Reading, initial (mL) = 5.57

Buret Reading, final (mL) = 25.25

Volume of Na2S2O3 dispensed (mL) = ________

Average molar concentration of Na2S2O3 (mol/L) = 0.025

Moles of Na2S2O3 dispensed (mol) = __________

Moles of I3- reduced by S2O32- (mol) = __________

Moles of O2 (mol) = __________

Mass of O2 (mg) = ___________

Dissolved oxygen, ppm O2 (mg/L) = ___________

Answer 1

I might have helped do ONE but not four where no effort has been made on any of them and nothing about what is understood etc. The last one isn't clear as to the problem. You're asking for someone to do all your work for you and I'm not interested in that.