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You have been most helpful.

Thank you very much.

Thanks! That solved my first problem.

Sorry about not knowing of the code env. and apparently posting too much code. Isn't there a possibility of different packages interacting with eachother causing that kind of problems? That's why I posted the whole preamble.

I did look into chemfig, but it ...

My preamble:
\documentclass[12pt,a4paper,twoside]{article}
\pagestyle{headings}
\usepackage{graphicx}
\usepackage[version=3]{mhchem}
\usepackage[super,square,numbers,sort&compress]{natbib}
\usepackage{textcomp}
\usepackage{subfig}
\usepackage{soul}
\usepackage{multirow}
%\usepackage{palatino ...