Électrolyse d'une solution de chlorure de sodium : illustrations

\documentclass{article}
\usepackage[a4paper,margin=2cm]{geometry}
\usepackage[T1]{fontenc}
\usepackage[latin1]{inputenc}
%\usepackage[garamond]{mathdesign}
\usepackage{pstricks,multido,pst-grad}
\input random
\definecolor{Orange}{rgb}{1,0.65,0}
\makeatletter
\newdimen{\BulleX}
\newdimen{\BulleY}
\newdimen{\hauteur}
\hauteur=2pt % hauteur maxi atteinte par les bulles les pts sont convertis en cm ensuite
\def\pstbulles#1{{% #1 = nombre de bulles
  \multido{\iBulle=1+1}{#1}{%
    \setrandim{\BulleX}{-0.15pt}{0.15pt}
    \setrandim{\BulleY}{0pt}{\hauteur}
    \pst@dimh=\BulleY
    \ifdim\BulleY>1.25pt \pst@dimh=1pt \fi
    \psdot[dotscale=\pointless\pst@dimh,dotstyle=o](! \pointless\BulleX\space
  \pointless\BulleY)}}}
\makeatother
\psset{dimen=middle}
\begin{document}
% le tube en U de diamètre 1cm
% de hauteur 5 cm
\def\psTubeU{%
        \pscustom[linestyle=none]{%
        \psline(-2,3)(-2,0)
        \psarc(0,0){2}{180}{0}
        \psline(2,0)(2,3)(1,3)(1,0)
        \psarcn(0,0){1}{0}{180}
        \psline(-1,0)(-1,3)(-2,3)}}
\def\psContourTubeU{%
       \pscustom[linewidth=2\pslinewidth]{%
        \psline(-2,3)(-2,0)
        \psarc(0,0){2}{180}{0}
        \psline(2,0)(2,3)}
       \pscustom[linewidth=2\pslinewidth]{%
        \psline(1,3)(1,0)
        \psarcn(0,0){1}{0}{180}
        \psline(-1,0)(-1,3)}}
%%%%%%%%%%%%%%%%%
 \def\electrode{
  \psframe*[linecolor=black](-0.1,0)(0.1,4.5)
  \psframe*[linecolor=Orange](-0.15,4.2)(0.15,4.5)}
\def\psVerrerie{
% tube à essais retourné
{\pscustom[linewidth=2\pslinewidth]{
\psline(-1.45,3.6)(-1.45,6.35)
\psarcn(-1.2,6.35){0.25}{180}{0}
\psline(-0.95,6.35)(-0.95,3.6)}
\psContourTubeU}
% tube à dégagement
\psline[doubleline=true,doublesep=1mm](-1.2,2)(-1.2,4.5)
% bouchon
\pspolygon[fillstyle=solid,fillcolor=gray!50,linewidth=0.025](-2.1,3.5)(-1.9,2.5)(-1.1,2.5)(-0.9,3.5)}
%
\begin{center}
\begin{pspicture}(-3,-2)(3,7)
\begin{psclip}{\psTubeU}
% liquide
\psframe*[linecolor=gray!20](-3,-2)(3,1.5)
\end{psclip}
\rput(-1.75,0){\electrode}
\psVerrerie
\psline(-1.7,4.5)(-3,4.5)
\psline(1.5,4.5)(3,4.5)
\rput(-3,4.5){\pscirclebox[fillstyle=solid]{$-$}}
\rput(3,4.5){\pscirclebox[fillstyle=solid]{$+$}}
\psframe[linestyle=none,fillstyle=solid,fillcolor=blue!50!magenta!50](1.025,0)(1.975,1.5)
\rput(1.5,0){\electrode}
\psline[linewidth=3\pslinewidth,linecolor=red]{->}(2.6,4.5)(2,4.5)
\uput[u](2.4,4.5){\red$I$}
\psline{->}(-3.1,0.75)(-1.25,0.75)
\uput[l](-3,0.75){phénolphtaléine}
\psline{->}(3.1,0.75)(2,0.75)
\uput[r](3,0.75){indigo}
\psline{->}(0,-2.5)(0,-1.5)
\uput[d](0,-2.5){solution de $\mathrm{Na^++Cl^-}$}
\end{pspicture}
\end{center}
\begin{center}
\begin{pspicture}(-3,-2)(3,8)
\begin{psclip}{\psTubeU}
% liquide
\psframe*[linecolor=gray!20](-3,-2)(3,1.5)
% dégagement de dichlore dans le tube
\psframe[linestyle=none,fillstyle=gradient,gradbegin=green!20,gradend=white,gradmidpoint=0](0,1.5)(3,3)
\end{psclip}
\rput(-1.75,0){\electrode}
\rput(1.5,0){\electrode}
\psVerrerie
\psline(-1.7,4.5)(-3,4.5)
\psline(1.5,4.5)(3,4.5)
\rput(-3,4.5){\pscirclebox[fillstyle=solid]{$-$}}
\rput(3,4.5){\pscirclebox[fillstyle=solid]{$+$}}
\psframe[linestyle=none,fillstyle=solid,fillcolor=blue!50!magenta!50](1.025,0)(1.975,1.5)
\pscustom[linecolor=gray!20]{\pscurve(1.3,1.5)(1.2,1)(1.3,-0.2)(1.4,-0.4)(1.7,0)(1.75,1)(1.7,1.5)\fill[fillstyle=solid,fillcolor=gray!20]}
\pscustom[linecolor=magenta]{\pscurve(-1.9,1.5)(-1.9,1)(-1.8,-0.2)(-1.4,0)(-1.5,1)(-1.5,1.5)\fill[fillstyle=solid,fillcolor=magenta]}%
\psframe*[linecolor=black](-1.85,0)(-1.65,1.5)
\psframe*[linecolor=black](1.4,0)(1.6,1.5)
\rput(-1.75,0){\hauteur=1.5pt\pstbulles{25}}
\rput(1.5,0){\psset{fillstyle=solid,fillcolor=green!20}\hauteur=1.5pt\pstbulles{25}}
\psline{->}(-1.2,4.6)(-1.2,5.5)\uput[u](-1.2,5.5){\small$\mathrm{H_2}$}
\psline[linewidth=3\pslinewidth,linecolor=red]{->}(2.6,4.5)(2,4.5)
\uput[u](2.4,4.5){\red$I$}
\psline{->}(-3.1,0.75)(-2,0.75)
\uput[l](-3,0.75){\shortstack{virage de la\\ phénolphtaléine}}
\psline{->}(3.1,0.75)(2,0.75)
\uput[r](3,0.75){\shortstack{décoloration de\\l'indigo}}
\psline{->}(3,2)(1.6,1.25)
\uput[r](3,2){dégagement de $\mathrm{Cl_2}$}
\psline{->}(-3,2)(-1.8,1.25)
\uput[l](-3,2){dégagement de $\mathrm{H_2}$}
\end{pspicture}
\end{center}
\end{document}