The CAS Registry Mumber 114819-97-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,4,8,1 and 9 respectively; the second part has 2 digits, 9 and 7 respectively. Calculate Digit Verification of CAS Registry Number 114819-97: (8*1)+(7*1)+(6*4)+(5*8)+(4*1)+(3*9)+(2*9)+(1*7)=135 135 % 10 = 5 So 114819-97-5 is a valid CAS Registry Number.