Question

just one example/demonstration!

Data needed to be calculated is in highlighted in green boxes. And I highlighted in red an equation (not sure if thats what you use to calculate it) And ignore the lab instructions on completeing a graph!! I already know how to do that in excel, just curious how Ln (relative rate) and 1/T in K^-1 is calculated by hand*

Effect of Temperature on the Reaction Rate: Determination of the Activation Energy The dependence of the rate constant with temperature is given by the equation below. In(k) +b where k is the relative rate constant, E is the activation energy, R is the Ideal Gas Constant in terms of energy, and T is the temperature in Kelvin Since the reactions at the different temperatures have the same concentrations, the rate constant will be equal to the observed relative rate constants. Plot the Ink) versus 1/T using a spreadsheet or by hand on graph. In Excel, add a trendline and show the linear regression and Rsquared Print the graph with appropriate labels for the axes and title. Calculate the activation energy and the Arrhenius or Frequency factor. Show your work below. Data for the Determination of the Activation Energy Approximate Temperature (°C) 0 10 20 23 40 292 Measured Temperature of Mixture (°C) Time in seconds for color to appear a to appear 0 435 12 343 137 41 ) 2.29 ate 2.91ek 7.29 an 24,39 Relative Rate 1000 LnRelative Rate) 1 708 616 410 314 Temperature in Kelvin 1/T in K Type (double-spaced) a discussion on your results. Discussion should include what you were studying, a brief description of experimental methods (not a step-by-step procedure), the results of the study and a comparison to "accepted" results (found by scarching online). No more than 2 typed pages should suffice.

here is the rest of that lab leading up to the question as I know its typically more helpful to read all the instructions:

thank you :) also what does why is -1 attached to K? thanks

Answer 1

values of relative rate and temperature and temperature are given and you wish to calculate ln(relative rate) and 1/T

ln x is the natural log of x where the base is e. It can be calculated with the help of a calculator or by looking up the values in a log table.

ln (2.29) = 0.8286, ln(2.91) = 1.068, ln (7.29) = 1.9865, ln (24.39) = 3.1942

To calculate 1/T:

1/708 K = 0.00141 K^-1 , 1/616 K = 0.00162 K^-1, 1/410 K = 0.00244 K^-1​​​​​​​, 1/314 K = 0.00318 K^-1​​​​​​​

Temperature is given in K so when 1/T is calculated the calculated quantity has units K^-1​​​​​​​ . The exponent -1 over K signifies that K is originally in the denominator.

1/K = K^-1​​​​​​​

After plotting ln k v/s 1/T activation energy can be found out by calculating the slope of the graph. It can be seen from the equation highlighted in red that the slope of the graph plotted between ln k and 1/T = -E_a/R

Because, Equation of a straight line: y = mx +b where y and x represent values on y and x-axis respectively, m is the slope of the line and b is the intercept.

Hope this helped! please upvote :)