The CAS Registry Mumber 141795-18-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,4,1,7,9 and 5 respectively; the second part has 2 digits, 1 and 8 respectively. Calculate Digit Verification of CAS Registry Number 141795-18: (8*1)+(7*4)+(6*1)+(5*7)+(4*9)+(3*5)+(2*1)+(1*8)=138 138 % 10 = 8 So 141795-18-8 is a valid CAS Registry Number.