Question

In the experiement, each flask containing a water sample, pipette 10.00 mL of the AgNO3 solution. Using a small graduated cylinder, carefully add 3.0 mL of Fe(NO3)3 solution and 2.0 mL of 6M HNO3 to each water sample. the trial is now ready for titration. Obtain approximately 120 mL of stock KSCN solution. Rinse out a clean buret with about 10 mL of KSCN at least twice, and discard the washing solution into a waste beaker.  From the calculation , number of moles of AgNO3 ( 0.05304 moles) that reacted with the chloride ( water sample) , calculate the concentration of chloride in the water sample. Express your results in mg/L. Report the final value to the appropriate number of significant figures.

Answer 1

Reaction:

Ag⁺+ Cl^-------------->AgCl (s)

from the experiment concentration of AgNO3 is given =0.05304 moles,

therefore from that given concentration we conclude that , one mole of silver nitrate reacts with one mole of chloride ion, that is the ratio of silver nitrate to chloride should be 1:1,

this means that, for 0.05304 moles of AgNO3, IT IS REQUIRED TO REACT with 0.05304 moles of chloride ion,

means there are 0.05304 moles of chloride ion present. Cl^-= MOL.WT=35.45,

FROM THAT WE CAN CALCULATE THE ACTUAL GRAMS OF CHLORIDE ION=0.05304*35.45=1.880 GRAMS/l,

then, convert that to mg/l,

1.880*/1000=1880.268 mg/l