ALREADY POSTED ONCE, ANSWERS WERE WRONG
1. Calculate the concentration of a solution obtained when 15.00mL of 2.04 E-3 M KMnO4 is measured from a buret into a 50 mLvolumetric flask which is then filled to the 50.0 mL graduationmark with distilled water.
2. A graph of absorbance vs. concentration yields a linearstandard curve for a set of standard solutions. Use the GRAPHICALANALYSIS program to plot the following absorbance (y) vs.concentration (x) data:
Absorbance: Concentratio(M)
0.245 6.00 XE-4
0.196 4.80 XE-4
0.147 3.60 X E-4
0.098 2.40 X E-4
0.049 1.20 X E-4
HINT: Theconcentration are so tiny that they will show up as zero in theGRAPHICAL ANALYSIS data table unless you change the display from 3places after the decimal to 3 significant figures. (This can bechanged after double-clickin gon the column heading.) What is theSLOPE of the graph?
3. Suppose that an unknown sample is analyzedspectrophotometrically (at the same wavelength as that used for thestandard curve measurements) and the absorbance was found to be0.194. Use the standard curve to determine the concentration of theunknown.
