QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - EXAMPLE 31.1 : As an approximation, let v = Zc / 137 where v is the radial velocity for 1 s electron of an element, c is the speed of light, Z is the atomic number. For gold with Z = 79, find the radial velocity of its 1 s electron, in term of c and percentage of the speed of light. (b) As an approximation, let A x A = 1 - Z x Z / 18769 where A is the ratio of the relativistic and non-relativistic Bohr radius. Find the value of A.

Answer / kangchuentat

QUANTUM CHEMISTRY AND CHEMICAL ENGINEERING - ANSWER 31.1 : (a) Approximately v = Zc / 137 = (79 / 137) c = 0.5766 c or 57.66 % of the speed of light. (b) Approximately A x A = 1 - Z x Z / 18769 = 1 - 79 x 79 / 18769 = 0.667 then A = 0.817. The answer is given by Kang Chuen Tat; PO Box 6263, Dandenong, Victoria VIC 3175, Australia; SMS +61405421706; chuentat@hotmail.com; http://kangchuentat.wordpress.com.

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