This is a direct quote from the Acer web site.
In order to remove a BIOS password your computer will need to be sent to Acer for repair. This service is not covered under warranty and password removal charges will apply to have the password removed. To set your computer up for repair service to have a BIOS password removed, please contact Acer support.
Holding down the F2 key at power on enters the BIOS if it is not password protected.
As other have suggested, if you want to do this your self, there will be a jumper to use, or on some systems, you have to remove the BIOS battery, and allow the BIOS to become reset. On some systems it can take some time for this to work. The battery I'm talking about looks like a quarter, its not the battery the system uses when not plugged in.
You have to disassemble the hardware and find it.
Acer doesn't seem to provide any hardware maintenance doc online. At least I couldn't fine it. I looked under Acer Aspire One. The model you provided is not listed.