翻訳と辞書 Words near each other ・ Arris, Batna ・ Arriscope ・ Arriscope (lens) ・ Arriscope (surgical microscope) ・ Arrissoules ・ Arrissoules Tunnel ・ Arritinngithigh language ・ Arrium ・ Arrius ・ Arriva ・ Arriva Buses Wales ・ Arriva Cristina ・ Arriva Derby ・ Arrhenius (Martian crater) ・ Arrhenius equation ・ Arrhenius plot ・ Arrheniusfjellet ・ Arrhenodes digramma ・ Arrhenophanes ・ Arrhenophanes perspicilla ・ Arrhenophanes volcanica ・ Arrhenophanidae ・ Arrhenoseius ・ Arrhenosphaera ・ Arrhenotoides dubouzeti ・ Arrhenotoky ・ Arrhephoria ・ Arrhichion ・ Arrhidaeus ・ Arrhinia Dictionary Lists mini英和辞書 mini和英辞書 Webster 1913 Latin-English FOLDOC Wikipedia English ウィキペディア

翻訳と辞書　辞書検索 [ 開発暫定版 ] スポンサード リンク Arrhenius plot ： ウィキペディア英語版 Arrhenius plot An Arrhenius plot displays the logarithm of kinetic constants ($\backslash ln(k)$, ordinate axis) plotted against inverse temperature ($1/T$, abscissa). Arrhenius plots are often used to analyze the effect of temperature on the rates of chemical reactions. For a single rate-limited thermally activated process, an Arrhenius plot gives a straight line, from which the activation energy and the pre-exponential factor can both be determined. The Arrhenius equation can be given in the form: :$k\; =\; A\; e^$ or alternatively :$k\; =\; A\; e^$ The only difference is the energy units: the former form uses energy/mole, which is common in chemistry, while the latter form uses energy directly, which is common in physics. The different units are accounted for in using either the gas constant $R$ or the Boltzmann constant $k\_B$. The former form can be written equivalently as: :$\backslash ln(k)\; =\; \backslash ln(A)\; -\; \backslash frac\backslash left(\backslash frac\backslash right)$ ::Where: :::$k$ = Rate constant :::$A$ = Pre-exponential factor :::$E\_a$ = Activation energy :::$R$ = Gas constant :::$T$ = Absolute temperature, K When plotted in the manner described above, the value of the true y-intercept (at $x\; =\; 1/T\; =\; 0$) will correspond to $\backslash ln(A)$, and the slope of the line will be equal to $-E\_a/R$. The values of y-intercept and slope can be determined from the experimental points using simple linear regression with a spreadsheet. The pre-exponential factor, A, is an empirical constant of proportionality which has been estimated by various theories which take into account factors such as the frequency of collision between reacting particles, their relative orientation, and the entropy of activation. The expression $e^$ represents the fraction of the molecules present in a gas which have energies equal to or in excess of activation energy at a particular temperature. == Worked Example == Based on the red "line of best fit" plotted in the graph given above: :Let y = ln(k(cm3 mol−1 s−1 )) :Let x = 1/T() Points read from graph: :y = 4.1 at x = 0.0015 :y = 2.2 at x = 0.00165 Slope of red line = (4.1 - 2.2) / (0.0015 - 0.00165) = -12,667 Intercept (at x=0'' ) of red line = 4.1 + (0.0015 x 12667) = 23.1 Inserting these values into the form above: :$\backslash ln(k)\; =\; \backslash ln(A)\; -\; \backslash frac\backslash left(\backslash frac\backslash right)$ yields: :$\backslash ln(k)\; =\; 23.1\; -\; 12,667\; (1/T)$ :$k\; =\; e^\; \backslash cdot\; e^$ as shown in the plot at the right. :$k\; =\; 1.08\; \backslash times\; 10^\; \backslash cdot\; e^$ for: :k in 10−4 cm3 mol−1 s−1 :T in K Substituting for the quotient in the exponent of $e$: :-Ea / R = -12,667 K ::approximate value for R = 8.31446 J K−1  mol−1 The activation energy of this reaction from these data is then: :Ea = R x 12,667 K = 105,300 J mol−1 = 105.3 kJ mol−1. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Arrhenius plot」の詳細全文を読む スポンサード リンク 翻訳と辞書 : 翻訳のためのインターネットリソース Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.