standalone.tex

% Tikz File 'mytikz.tex'
\documentclass{standalone}
\usepackage{tikz}
\usepackage{pgfplots}
\usepackage{epstopdf} %include eps Drawings from LaTeX Drawing Programs
\usepackage{mathtools}
\newcommand{\defvar}{\vcentcolon=} %Use command /defvar for define symbol
\begin{document}
\begin{tikzpicture}
\begin{axis}[
    %title={Temperature dependence of CuSO$_4\cdot$5H$_2$O solubility},
    xlabel={$T/\SI{}{\kelvin}$},
    ylabel={$p/\SI{}{\bar}$},
    xmin=345, xmax=400,
    ymin=0.2, ymax=2.2,
    %xtick={0,20,40,60,80,100},
    %ytick={0,20,40,60,80,100,120},
    legend style={font=\small},
    legend pos=north west,
    ymajorgrids=true,
    grid style=dashed,
]
\addplot+[
mark=*,
mark options={blue},
error bars/error bar style={blue},
only marks, error bars/.cd,
x dir=both,x explicit,
y dir=both,y explicit,
]
table[x=x,x error=xerror,y=y,y error=yerror]
{
x           xerror   y          yerror
353	1	0.4736	0.0001
363	1	0.701	0.0001
373	1	1.0133	0.0001
383	1	1.4327	0.0001
393	1	1.9583	0.0001
};
\addlegendentry{Druck Wasserdampf}
\addplot [
	restrict y to domain=0.2:3,
    domain=-345:400, 
    samples=300, 
    color=red,
]
{-0.28516+4.99E-05*exp(-x/-36.67958)};
\addlegendentry{Exponentieller Fit}
\end{axis}
\end{tikzpicture}
\end{document}