I'll be happy to answer your question but I need more specific information about your computer. Top left of desktop go to the apple logo, about this Mac, more info. You should see something like "13-inch, Early 2011". The RAM that works depends on a few factors so I need more specific information from you just to be sure. You can check here if you like: (it will tell you what is compatible)
not sure of that specific model but what i did was to nav to crucial.com and use their drop-down menu pages to guide me in the proper selection of the kit2fit my 2011 mbp...it was helpful to get the scoop from your mbp's "about this mac" spec list by clicking the apple icon in the top left corner of your mbp on-screen.
Yes, it should according to other reviewers here on Amazon. http://www.amazon.com/review/R36D3A6AJMH90V/ref=cm_cr_pr_perm?ie=UTF8&ASIN=B003DZJQQI&linkCode=&nodeID=&tag= is one such review. Memory is a tricky thing at times with the Macbook Pros for some reason, but this should work as long as Crucial is shipping the speed specified. Sometimes manufacturers ship faster RAM because most machines can run faster memory fine, especially Windows machines, but Macs are a lot more picky when this happens. Hope that helps!
i don't know for sure - you should find your MBP on this chart: http://support.apple.com/kb/HT1270
i selected the 2009 2.53ghz model (although there are many other 2009 models) on the list and it looks like the max RAM on that one is 2 x 2GB, so if your MBP is the same model, then no, this particular product isn't what you are looking for because it's two (2) 4GB. you could however buy the crucial 4GB kit (2GBx2) instead. (such as this: Crucial CT2KIT25664BC1067 4GB 204-PIN PC3-8500 SODIMM DDR3 Memory KIT (2GBx2) )
I don't have a mac so don't hold me responsible for the accuracy of this answer but one of 3 things is likely to happen if you install it correctly: 1. It won't work at all and possibly damage your laptop somehow. 2. It will run at a reduced speed (relative to the memory's maximum capability) because your laptop can't fully utilize it. 3. It will run at full speed (again relative to the memory's capability) because your laptop can fully utilize it.