Question

Hg2+ + 2Cl- → HgCl

Mercuric nitrate was standardized by titrating a solution containing 147.6 mg of NaCl(FM 58.44), which required 28.06 ml of Hg(No3)2 solution.

Part a: Find the molarity of Hg(No3)2.

I already calculated the molarity to be 0.04500 M

Part b: When the same Hg(No3)2 solution was used to titrate 2.00 mL of urine, 22.83 mL was required. What is theconcentration of Cl- (mg/mL) in urine.

I know the answer for part b is 36.42 mg/ml, but I'm not sure exactly how to get there...

Thanks.

Answer 1

1)Calculate the molarity for the mercuric nitrate solution. =0.04500M

2)Use M1V1=M2V2, to find urine concentration. (0.045mol/L)(0.02283L)=(M2)(0.002L), M2=0.513675mol/L

3)Find concentration of Cl using titration equation molecular ratios and molecular mass of Cl.
(0.513675molUrine/L)*(1molHgCl2/1molUrine)*(2molCl/1molHgCl2)*(35.453gCl/1molCl)*(1L/1000mL)*(1000mg/1g)=36.42mg/mL

Answer 2

0.18

Answer 3

Asuna, How did you calculate the Molarity of in part A?