The CAS Registry Mumber 85319-50-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,5,3,1 and 9 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 85319-50: (7*8)+(6*5)+(5*3)+(4*1)+(3*9)+(2*5)+(1*0)=142 142 % 10 = 2 So 85319-50-2 is a valid CAS Registry Number.