The CAS Registry Mumber 85918-19-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,5,9,1 and 8 respectively; the second part has 2 digits, 1 and 9 respectively. Calculate Digit Verification of CAS Registry Number 85918-19: (7*8)+(6*5)+(5*9)+(4*1)+(3*8)+(2*1)+(1*9)=170 170 % 10 = 0 So 85918-19-0 is a valid CAS Registry Number.