I bought the wrong chip.

Question

This is more of a hypothetical question.  I ask because I am curious.
My Mid-2010 Mac Mini worked cheerfully on 2GB of RAM until I got to Yosemite.  Since then the computer has been getting slower and slower.  When my HP LaserJet P1102w refused to print any more PDFs, I decided to "look under the hood."  Activity Monitor reported that I was using 2.94GB of Virtual Memory.   No wonder the Mini was slow.  I went to the store for more RAM.   Somewhere along the way, I got confused about the model year of the Mini.  I asked the sales clerk for 8GB for a Mid-2011 Mini.  He sold me what I thought was two 4GB modules.  When I got back to the Mini, I opened the package and found one 8GB module.   Not wanting to spend any more time on the project than I had already, I removed the two original 1GB modules from the Mini and installed the 8GB one.   It worked.   The Mini did everything I wanted except to print a PDF.   Quickly I determined that I had asked for the wrong modules.  I went back to the store and exchanged the one wrong 8GB module for two 4GB modules.   And the Mini is running again.
The questions I have are:
1)  Could I have continued to run the Mini on only one 8GB module?
2)  Could I have installed a second 8GB module?
BTW, the HP continues to refuse to print PDFs.  

Answer 1

Yes, and Yes.
Maximum Memory
16 GB (Actual) 8 GB (Apple)
Memory Slots
2 - 204-pin PC-10600 (1333 MHz) DDR3 SO-DIMM
The above is what you can install in the 2011 Mini.