The CAS Registry Mumber 79023-52-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,9,0,2 and 3 respectively; the second part has 2 digits, 5 and 2 respectively. Calculate Digit Verification of CAS Registry Number 79023-52: (7*7)+(6*9)+(5*0)+(4*2)+(3*3)+(2*5)+(1*2)=132 132 % 10 = 2 So 79023-52-2 is a valid CAS Registry Number.