In Part 3 you will weigh out 3 samples of unknown sample, and titrate them to determine the exact concentration of your periodate standard to 4 significant figures. Here is your data: Your first unknown sample weighed 1.0438 grams. The burette starting volume was 2.70 mLs The burette reading at the titration end point was 19.51 mLs. Calculate your unknown concentration in units of wt%. Your second unknown sample weighed 1.0466 grams. The burette starting volume was 2.90 mLs The burette reading at the titration end point was 19.76 mLs. Calculate your unknown concentration in units of wt%. Your third unknown sample weighed 1.0396 grams. The burette starting volume was 2.38 mLs The burette reading at the titration end point was 19.25 mLs. Calculate your unknown concentration in units of wt%. Calculate and report the average Fe wt% in your unknown sample. %