Question

The radioisotope ⁹⁹₄₃Tc is an isotope that is sometimes given to patients because it emits gamma rays and has a relatively short half-life of 6.05 h. Because it emits gamma rays, ⁹⁹₄₃Tc can be used as a tracer when performing imaging on a specific part of the human body.

(a)Find the decay constant of ⁹⁹₄₃Tc (in h⁻¹).Answer should have h^-1 units

(b)Find the number of ⁹⁹₄₃Tc nuclei needed to provide an activity of 1.53 µCi. Units in nuclei

Answer 1

(a)

=0.693/6.05

= 0.114

(b)

Activity ,

A = 1.53

= 1.53 ×(3.7×) Bq

= 5.66× Bq

0.114 = 0.114/h

= 0.114/(3600 s)

= 3.18×

Putting values ,

N = 1.78×