Microsoft Word tutorial origin doc

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INTRODUCTION TO ORIGIN 
(DATA ANALYSIS AND PLOTTING SOFTWARE) 
(UPDATED 
01/12/09) 
Origin (Microcal Software, Inc., One Roundhouse Plaza, Northhampton, MA 01060) is one of several 
software packages designed specifically for plotting and analyzing quantitative data. You will be using 
Origin for a variety of applications in this course. Purposes of this document are to introduce you to two of 
the primary capabilities of ORIGIN software, namely plotting and curve-fitting capabilities, and to illustrate 
applications of Origin in conjunction with spread-sheet programs such as Microsoft EXCEL.
Data for the spectrophotometric determination of ferrous iron (Table 1, Columns A – E) and masses 
of paper clips (Table 1, Columns F and G) are used to illustrate applications of the Origin software to both 
linear and nonlinear data sets. Data in the first three columns represent experimentally determined values 
of absorbance and percent transmittance for different Fe(II) concentrations treated with 1,10-
phenanthroline under appropriate conditions (See text.). Data in the fourth column represent realistic 
absorbance errors for a spectrophotometer good to 
± 0.2 %T. Data in the fifth column are exaggerated (x 
10) transmittance errors; exaggerated values are used to aid in visualization. The data are to be entered 
into columns A(X) and B(Y) through E(Y) of an Origin worksheet using procedures described below. 
Origin will be used to plot the data and to fit suitable models to the plotted data. The figure at the end of 
this presentation illustrates a formatted plot of absorbance vs. concentration with a least-squares line 
included. 
Table 1. Numerical data used to illustrate basic applications of data analysis and plotting software. 
Concn. 
(10
-4
mol/L) 
A 
(au)
a
T
(%) 
Error (au) 
Error 
(%T) 
Mass 
(g) 
Number of 
values 
A(X) B(Y) C(Y) D(Y) E(Y) F 
G 
0 0.000 
100 
0.00087 
2 
0.4621 1 
0.0226 0.0438 90.5 0.00095 2 0.4632 
7 
0.0458 0.0615 86.8 0.001 
2 0.4644 
17 
0.0915 0.1238 75.2 0.0011 2 0.4655 
16 
0.229 0.292 51 0.0017 2 0.4667 
9 
0.458 0.595 25.4 0.0034 2 0.4679 
1 
0.915 1.167 6.8 0.013 2 
1.84 2.22 0.6 0.12 2 
2.5 3.01 0.1 0.48 2 
a
Although absorbance is a unitless quantity, it will be helpful to imply units, au, in expressions
involving absorbance.