{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

2800hw3 - Brittney Brown Calibration Methods Partner Erica...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Brittney Brown September 29, 2010 Calibration Methods Partner: Erica Francis Table 1. Raw data for the Absorbance Outliers were found in the data and were removed. The plot of the average absorbance and the plot of the raw data had different R 2 values but the same linear equation. The plot of the average absorbance is a better representation of the data and the linear line is a better fit for the data points noted by the higher R 2 value (0.999) when comparing the two graphs. Table 2. Calculated values of unknown by External Standard and Standard Additions Group # Concentration of Unknown by External Standards Concentration of unknown by Standard Addition 2 8.72 7.719 3 7.29 7.220 4 7.82 6.916 5 7.50 7.468
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
7 9.07 9.049 8 7.87 4.444 9 7.66 6.195 10 9.84 7.783 11 7.96 7.433 The two methods produce statistically different results at t stat=2.81, df=8, t table= 2.306. External standardization is different from the standard addition method. Standard addition is when known quantities of analyte are added to the unknown sample. How much analyte was present in the original unknown can be determined by the increase in signal.
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}