Question: Is there any way in which I can include structures of molecules (line diagrams) in the question? It would be helpful to clarify the question to a greater extent.

Answer: 
I usually use [ChemDoodle](http://web.chemdoodle.com/demos/sketcher)

There is a plan in the pipeline to integrate ChemDoodle into the editor, but I don't have the time to get working on that right now.
Most of my answers concerning organic chemistry contain a structure or two ;-)

I use [BKChem](http://bkchem.zirael.org/) under GNU/Linux, installed from a repo.
I save the sketches as SVG and export them to transparent PNG for upload.

There seem to be tarballs and installers for Windows and Mac OS too, but I haven't tried those - personally I'm not interested in these platforms.