How to have more Workspaces created/removed Automatically?
I am guessing you are using Unity. This idea is a feature in the Gnome-3 desktop environment see the right column on the image below - workspaces are added and removed as necessary. In this case there are two, but if the user puts something in the second workspace, a third one is created.). 
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To install the gnome-shell, use these commands here:
- How do I install and use the latest version of GNOME?
Then, log-out and before you log back in, change your desktop by clicking on the Ubuntu icon near your login name. Here are more detailed instructions.