The CAS Registry Mumber 118648-07-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,8,6,4 and 8 respectively; the second part has 2 digits, 0 and 7 respectively. Calculate Digit Verification of CAS Registry Number 118648-07: (8*1)+(7*1)+(6*8)+(5*6)+(4*4)+(3*8)+(2*0)+(1*7)=140 140 % 10 = 0 So 118648-07-0 is a valid CAS Registry Number.