IBstudent8888 Posted June 26, 2019 Report Share Posted June 26, 2019 My chemistry IA investigates the different activation energy of the decomposition of H202 with Lead oxide and manganese oxide. My teacher told me to plot 1/Temp against Ln x 1/ Average Time taken but not how to actually calculate Ea. How do I get the activation energy if I have the time it takes for the percentage of oxygen to rise by 15% at 5 different temperatures and have it plotted 1/Temp against Ln x 1/ Average Time taken using the Arrhenius equation. Reply Link to post Share on other sites More sharing options...
kw0573 Posted June 27, 2019 Report Share Posted June 27, 2019 From the Arrhenius equation, k = A exp (-Ea/(RT)), taking ln of both sides ln k = ln A - Ea/(RT) = -(Ea/R) T + ln A, which is the equation of a line with slope -Ea/R and vertical intercept of ln A. So if you know the slope you can find the activation energy k is the rate constant such that the "rate of change of [H2O2]" = Δ[H2O2]/Δt = k [H2O2] (first order rate law). By unit analysis, k has dimension of inverse time. Hope that helps. There should also be videos online of teachers walking through the data processing. Reply Link to post Share on other sites More sharing options...
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