The CAS Registry Mumber 88626-86-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,8,6,2 and 6 respectively; the second part has 2 digits, 8 and 6 respectively. Calculate Digit Verification of CAS Registry Number 88626-86: (7*8)+(6*8)+(5*6)+(4*2)+(3*6)+(2*8)+(1*6)=182 182 % 10 = 2 So 88626-86-2 is a valid CAS Registry Number.