excel~~last post :'(

INTRODUCTION

EXCEL is a spreadsheet application written and distributed by Microsoft for Microsoft Windows and Mac OS X.Its features includes calculation ,and graphing tools,and also It has been a very widely applied spreadsheet for these platforms, especially since version 5 in 1993.It is useful in these days especially when you are working in companies.

PART 1 : BEER'S LAW SCATTER PLOT AND LINEAR REGRESSION

Beer's Law states that there is a linear relationship between concentration of a colored compound in solution and the light absorption of the solution. This fact can be used to calculate the concentration of unknown solutions, given their absorption readings. First, a series of solutions of known concentration are tested for their absorption level. Next, a scatter plot is made of this empirical data and a linear regression line is fitted to the data. This regression line can be expressed as a formula and used to calculate the concentration of unknown solution.

PART 2: TITRATION DATA PLOTTING

Creating a Scatter Plot of Titration Data

In this next part of the tutorial, we will work with another set of data. In this case, it is of a strong acid-strong base titration. With this titration, a strong base (NaOH) of known concentration is added to a strong acid (also of known concentration, in this case). As the strong base is added to solution, its OH- ions bind with the free H+ions of the acid. An equivalence point is reached when there are no free OH- nor H+ ions in the solution. This equivalence point can be found with a color indicator in the solution or through a pH titration curve.