Adding my own file extension

If am fairly new to word press and I wan’t to know if it is possible to add my own file extension when I post something. For instance, the URL for one of my webpages looks like this: http://www.tostopaforeclosure.com/?p=247 and I want to make the file extension something that is relevant to the article like “Bankruptcy”, so the URL would read:http://www.tostopaforeclosure.com/bankruptcy. I am sure it would be helpful for SEO purposes.

Thanks