1 Pmol (petamole) is equal to 0.000000000000000000000000000000000000001 Ymol (yottamole). To convert from petamole to yottamole, multiply by 0.000000000000000000000000000000000000001 or divide by 1,000,000,000,000,000,100,000,000,000,000,000,000,000.