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1 g of   79 Au 198 t 1/2 =65 h give stable mercury by β - emission. What amount of mercury will left after 260 h?

Options

  1. A0.9375 g
  2. B0.3758 g
  3. C0.7586 g
  4. D0.9000 g

Correct answer

A. 0.9375 g

Step-by-step solution

79 A u 198 → - B 80 H g 198 k   =   0 .693 t 1/2   =   0 .693 65 After 260 hr, k   =   2 .303 260   log   a a − x 0 .693 65   =   2 .303 260   log   a a − x a a − x   =   16   1 1 − x   =   16 x   =   15 16   g   =   0 .9375 g

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