The decay constant for a radioactive nuclide is 1 . 5 × 10 - 5 s - 1 . Atomic weight of the substance is 60 g mole - 1 , N A = 6 × 10 23 . The activity of 1 . 0 µ g of the substance is ________ × 10 10 Bq .

Step-by-step solution

It is given that λ = 1 . 5 × 10 - 5   s - 1 Number of moles is 1 × 10 - 6 60 = 10 - 7 6 Number of atoms=number of moles × N A N 0 = 10 - 7 6 × 6 × 10 23 = 10 16 Hence, at t = 0 ,   A = A 0 = N 0 λ , the activity can be given by A = N 0 λ e - λ t ⇒ A = 10 16 × 1 . 5 × 10 - 5 × 1 = 15 × 10 10   B q