As StevenP correctly noted, it's not technically an acid...It's alkaline which is a base. Think back to your chemistry days...what do you neutralize a base with? Acid!
So, get you some vinegar (an acid) and slightly dilute it with water. Pour it in a cookie tray with enough depth and soak the board in it. Scrub any of the alkaline corrosion off with a toothbrush. Rinse thoroughly with water and then blow out with a compressor or air can and let air dry afterwards.
You want to make sure you get moisture out from between the pins and underneath the ICs.
Edit: D'oh beat to the punch by RWH