Lab41

Experiment 7: Analysis of an Unknown Chloride

Objectives
Experimental
The objective of this experiment was to identify the molarity of a solution of chloride.
Laboratory
In lab we had to perform titrations and carefully read the burets.
Data and Calculations: Analysis of Unknown Chloride
Molarity of Standard AgNo3 solution 0.02785M I II III Initial buret reading 0.00 mL 0.00 mL 0.10 mL

Final buret reading 17.00 mL 16.40 mL 17.50 mL

Volume of AgNo3 used to titrate sample 17.00 mL 16.40 mL 17.40 mL No. of moles of
AgNo3 used to titrate sample mol=VxM mol=VxM mol=VxM 0.01700Lx0.02785mol/L 0.01640Lx0.02785mol/L 0.01740Lx0.02785mol/L 4.735x10-4mol 4.567x10-4mol 4.846x10-4mol No. of moles of
Cl – present in sample 4.735x10-4mol 4.567x10-4mol 4.846x10-4mol Volume of diluted chloride sol. pipetted 10mL 10mL 10mL Total moles of Cl- in 100mL vol flask 4.735x10-3mol 4.567x10-3mol 4.846x10-3mol Cl-concentration in diluted solution in volumetric flask M=mol/L M=mol/L M=mol/L =4.735x10-3mol =4.567x10-3mol =4.846x10-3mol .01L .01L .01L =0.4735 M =0.4567 M =0.4846 M

Mean chloride concentration =0.4716 M Unknown number Cl-13

Discussion
In this lab we are trying to find the amount of Cl- in a sample we know that Ag+ will bond with Cl- with a 1 to 1 ratio to form a precipitate. When we go from grams of Ag+ to moles of Cl- we can find out how much Cl- was in the unknown