Sadly, I am not that familiar with mobile CPUs and upgrades paths, so can not really suggest a upgrade path.
Other than it would need to be a Core2Duo family Chip.
The i3 uses a different socket than Core2, therefore would not work.
Soryy couldn't be more help, but Im sure someone much smarter than I will be along shortly who can help
The chance of updating the processor in your laptop is extremely unlikely, and basically impossible for several reasons.
Laptops are not designed or built for changing processors, many have it soldered in place. Any such work must be done by the manufacture.
The entire line of processors that your's is a part of has been retired and is no longer manufactured.
The "i3" processor you mentioned uses a different socket (size and layout of it's connections) and is incompatible with the one in your laptop. That socket is no longer used.
If you could find a processor that was compatible physically with your laptop, the BIOS software in your laptop may not support it. That information can only come from Acer.
The price of the work to change processors would be at about 50% of what a new laptop would cost.
All this applies to the vast majority of laptops, so you didn't buy a bad one, that is simply the way they are, sorry to say.