0
You visited us 0 times! Enjoying our articles? Unlock Full Access!
Question

# The specific activity of a preparation consisting of radioactive $$Co^{58}$$ and nonradioactive $$Co^{59}$$ is equal to $$2.2 \cdot 10^{12}$$ dis/(s $$\cdot$$ g). The half life of $$Co^{58}$$ is $$71/3$$ days. Find the ratio of the mass of radioactive cobalt in that preparation to the total mass of the preparation (in per cent).

Solution
Verified by Toppr

#### We see that Specific activity of the sample $$= \dfrac{1}{M + M'}$$ [ Activity of $$M\,gm$$ of $$Co^{58}$$ in the sample]Here $$M$$ and $$M'$$ are the masses of $$Co^{58}$$ and $$Co^{59}$$ in the sample. Now activity of $$M\,gm$$ of $$Co^{58}$$ $$= \dfrac{M}{58} \times 6.023 \times 10^{23} \times \dfrac{ln\ 2}{71.3 \times 86400}$$ dis/sec $$= 1.168 \times 10^{15} M$$Thus from the problem $$1.168 \times 10^{15} \dfrac{M}{M + M'} = 2.2 \times 10^{12}$$ or $$\dfrac{M}{M + M'} = 1.88 \times 10^{-3}$$ i.e., $$0.188\%$$

0
Similar Questions
Q1
The specific activity of a preparation consisting of radioactive $$Co^{58}$$ and nonradioactive $$Co^{59}$$ is equal to $$2.2 \cdot 10^{12}$$ dis/(s $$\cdot$$ g). The half life of $$Co^{58}$$ is $$71/3$$ days. Find the ratio of the mass of radioactive cobalt in that preparation to the total mass of the preparation (in per cent).
View Solution
Q2
The activity of a freshly prepared radioactive sample is 1010 disintegrations per second, whose mean life is 109 s. The mass of an atom of this radioisotopes is 1025kg. The mass (in mg) of the radioactive sample is .....
View Solution
Q3
A $$U^{238}$$ preparation of mass $$1.0\,g$$ emits $$1.24 \times 10^{4}$$ alpha-particles per second. Find the half-life of this nuclide and the activity of the preparation.
View Solution
Q4
A certain prepartion includes two beta-active components with different half lifes . the measurements resulted in the following dependence of the natural logarithm of preparation activity on time t expressed in hours. find the half-lifes of both components and the ratio of radioactive nuclei of these components at the moment t=0

View Solution
Q5
The activity of a freshly prepared radio-active sample is 1010 disintegrations per second, whose mean life is 109s. The mass of an atom of this radio-isotope is 1025 kg. The mass (in mg) of the radioactive sample is
View Solution