The CAS Registry Mumber 681482-52-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 6,8,1,4,8 and 2 respectively; the second part has 2 digits, 5 and 2 respectively. Calculate Digit Verification of CAS Registry Number 681482-52: (8*6)+(7*8)+(6*1)+(5*4)+(4*8)+(3*2)+(2*5)+(1*2)=180 180 % 10 = 0 So 681482-52-0 is a valid CAS Registry Number.