The CAS Registry Mumber 68346-09-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,8,3,4 and 6 respectively; the second part has 2 digits, 0 and 9 respectively. Calculate Digit Verification of CAS Registry Number 68346-09: (7*6)+(6*8)+(5*3)+(4*4)+(3*6)+(2*0)+(1*9)=148 148 % 10 = 8 So 68346-09-8 is a valid CAS Registry Number.