The CAS Registry Mumber 78114-50-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,8,1,1 and 4 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 78114-50: (7*7)+(6*8)+(5*1)+(4*1)+(3*4)+(2*5)+(1*0)=128 128 % 10 = 8 So 78114-50-8 is a valid CAS Registry Number.