The CAS Registry Mumber 2572-07-8 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 2,5,7 and 2 respectively; the second part has 2 digits, 0 and 7 respectively. Calculate Digit Verification of CAS Registry Number 2572-07: (6*2)+(5*5)+(4*7)+(3*2)+(2*0)+(1*7)=78 78 % 10 = 8 So 2572-07-8 is a valid CAS Registry Number.