[Vermilion]

Im in second year analytical chemistry and during lecture we have just been going over stat formulas like Standard deviation, Regression, etc and the questions im supposed to do in the textbook are totally foreign. I was wondering if someone could help me out or at least tell me where to start?

Question: A study was done to determine the activation energy E_A for a chemical reaction. The rate constant k was determined as a function of temperature T, and the data in the following table were obtained.

Temperature, T, K                                                         k,s^-
          599                                                              0.00054
          629                                                              0.0025
          647                                                              0.0052
          666                                                              0.014
          683                                                              0.025
          700                                                              0.064

The data should fit a linear model of the form log k = log A - E_A/(2.303RT), Where A is preexponential factor and R is the gas constant.

(a) Fit the data to a straight line of the form log k = a - 1000b/T

(b) Find the slope, intercept, and standard error of the estimate.

(c) Noting that E = -b X 2.303R X 1000, find the activation energy and its standard deviation. (Use R = 1.987 cal mol^- K^-.)

Relevant table of equations:
Function                                                  Transformation to linearize          Resulting Equation
Exponential: y = be^mx                    y' = ln(y)                          y' = ln(b) + mx
power:         y = bx^m                     y' = log(y), x' = log(x)       y' = log(b) + mx'
Reciprocal:   y =  b+ m(1/x)          x'= 1/x                             y= b + mx'

additional  notes: a = intercept, b = slope

much help needed, thanks

[Borek]

No idea what you were told during the lecture - but you were either given formulas for use for linear regression, or you were pointed to the software to use.

[Prim]

You need to plot this in Excel or some other software (Prism etc) - you need to plot as a graph and obtain the equation of the line

y=mx+c

http://www.mathsisfun.com/equation_of_line.html

There are further help files in the sofware - or failing that you could google 'how to plot a graph in Excel' etc