A samll amount of solution containing Na^(24) radio nuclide with activity A = 2xx10^(3) dps was administeredinto blood of a patientin a hospital. Afer 5 hour a sample of the blooddrawn out form the patientshowed an activity of 16 dpm per cc t_(1//2) for Na^(24) = 15 hr. Find: (a) Volume of the blood in the patient. (b) Activity fo blood sample drawn after a further time fo 5 hr.

A samll amount of solution containing Na^(24) radio nuclide with activ

1.	A samll amount of solution containing Na^(24) radio nuclide with activity A = 2xx10^(3) dps was administeredinto blood of a patientin a hospital. Afer 5 hour a sample of the blooddrawn out form the patientshowed an activity of 16 dpm per cc t_(1//2) for Na^(24) = 15 hr. Find: (a) Volume of the blood in the patient. (b) Activity fo blood sample drawn after a further time fo 5 hr.
Answer» Solution :Let `V mL` blood is present in patient. (a) `r_(0)` pf `Na^(24) = 2xx10^(3) DPS = 2xx10^(3) xx 60 dp m` `= 120xx10^(3) dp m` for `V mL` blood `r` of `Na^(24) = 16 dp m//mL` at `t = 5 HR` `= 16xx V dp m//V mL` `:' (r_(0))/(r) = (N_(0))/(N)` `:. (N_(0))/(N) = (120xx10^(3))/(16V)` `:. t = (2.303)/(lambda) log_(10) ((N_(0)))/(N)` `5 = (2.303xx15)/(0.693) log_(10)((120xx10^(3)))/(16V)` `:. V = 5.95 xx10^(3) mL` (b) Activity of blood sample after`5 hr` more i.e., `t = 10 hrt` `t = (2.303)/(lambda) log_(10) (N_(0))/(N)` `10 = (2.303xx15)/(0.693) log_(10) (120xx10^(3))/(A)` `:. A = 75.6xx10^(3) dp m` per `5.95 xx10^(3)mL` `= (75.6xx10^(3))/(5.95xx10^(3)) = 12.71` dpm per `mL`. `= 0.2118` dpm per `mL`.