The CAS Registry Mumber 119935-34-1 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,9,9,3 and 5 respectively; the second part has 2 digits, 3 and 4 respectively. Calculate Digit Verification of CAS Registry Number 119935-34: (8*1)+(7*1)+(6*9)+(5*9)+(4*3)+(3*5)+(2*3)+(1*4)=151 151 % 10 = 1 So 119935-34-1 is a valid CAS Registry Number.