solve only Question 5(dont solve it if you are not sure)

1. A water sample has 122mg/L of bicarbonate ion (HCO3),30mg/L of carbonate ion (CO3). (20 Pts) a. Please find the pH at equilibrium graphically. b. How would pH change if NaOH is added? c. What is the pH range corresponding to molar HCO3 concentration being 10 times higher than and equal to molar CO3 ' concentration. H:1g/mole,C:12g/mole,O:16g/mole Ka1=106.35Ka2=1010.33 2. A solution is prepared that has 103MNaCl (s) and 103MCa(OH)2 (s). (20 Pts) a. What is the ionic strength of solution if both salts are completely dissolved. b. We know that Ca(OH)2(s) is in fact sligthly soluble. What is the ionic strength of solution if 30% of added Ca(OH)2(s) has dissolved and 90%NaCl(s) has dissolved. c. What is the concentration of NaCl (s) before any dissolution occurs? I=0.5i=1ncizi2 3. To what pH must a solution be adjusted to cause >95% of TOTAc to be present as the neutral acetic acid molecule (HAc)?pKa=4.76 (20 Pts) 4. A solution is made by adding 102.5MHOCl and 103MNaPr to water. Then NaOH is added until the solution pH is 9 . How much NaOH must be added in mg/L ? (20 Pts) Na: 23g/mole,0:16g/mole,H:1g/mole 5. Please draw the log CpH diagram for Fe3+ in a solution that contains 103M TOTFe. Use Excel. Hint: check page 368 in your textbook. (20 Pts)