No. They are not pin-compatible, and you will most likely damage the chip, the board, or both. In order to get 2 megabytes of chip memory in an A2000 you need one of the "MegaChip" boards.
http://www.discreetfx.com/Amiga%20Resource/Amiga%20Resource/AMIGA_RE/EXP/MEGACHIP.HTMThese come up on Ebay and Amibay pretty frequently. Disregard the part in that link above where it says "rules out internal processor cards", that's not accurate. MegaChip works fine for adding 2MB of chip memory and are pretty much 100% hardware compatible, except maybe with something else that mounts in the Agnus socket.
