Question

(a) How can you manipulate the size of activation barrier we discussed today? Describe by discussing Figure 3.8.

Figure 3.8 If the Galvani potential across a reaction interface is reduced, the free energy of the forward reaction will be favored over the reverse reaction. While the chemical energy (a) of the reac tion system is the same as before, changing the electrical potential (b) upsets the balance between the forward and reverse activation barriers (c). In this diagram, reducing the Galvani potential by "'educes the forward activataon barrier «Δ < Δ G") and increases the reverse activation barrier At equilibrium, the current densities for the forward and reverse reactions are both given by jo- Away from equilibrium, we can write the new forward and reverse current densities by starting fromjo and taking into account the changes in the forward and reverse activation barriers: (3.30) (3,.31) The net currentG-J)is then (3.32) E® Distance () Ap Distance Distance () Ib)
(b) If you apply voltage “X” then by what amount forward and backward activation energy barrier will decrease.

(c) What is transfer coefficient “α” and how it is connected with the barrier shape?

Answer 1

bstract The visible part (≈ 419 − 696 nm) of the multiline electronic-vibro-rotational emission spectrum of the D2 molecule was recorded with moderate resolution mainly limited by Doppler broadening of spectral lines (line widths FWHM less than 0.013 nm). After numerical deconvolution of the recorded intensity distributions and proper calibration of the spectrometer the new set of wavenumber values was obtained. It is shown that new data are significantly more precise than those available for visible part of the D2 spectrum. Final results are reported as a supplement in the form of an atlas divided into 158 sections (each section covers about 1.5 nm) containing pictures of images in the focal plane of the spectrometer, intensity distributions in linear and logarithmic scales and the table containing wavenumber and relative intensity values for 11941 spectral lines together with available and new line assignments for the D2 and HD molecules. Keywords: Deuteruim, molecule, visible, emission, spectrum, atlas