Exercises+with+Amount+of+Radioactive+Material+(number+of+nuclei,+number+of+moles,+weight)+and+the+Law+of+Radioactive+Decay



Calculate the rate of disintegration of the following:
 * 1: **
 * 1) 1.0 • 10 13 atoms 99m Tc.
 * 2) 1.0 • 10 14  atoms 14 C.
 * 3) 1.0 grams 239 Pu.
 * 4) 1.0 gram 235 U.


 * 2: **

Calculate the amount of atoms of the following nuclei, based on their activity:


 * 1) 10 MBq of 32 P
 * 2) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">200 kBq of 131 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">I


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">3: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">A source of 60 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Co has a rate of disintegration equal to 1.0 • 10 14 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> Bq. What is the mass of 60 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Co in grams?


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">4: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">A preparation labelled 3 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">H disintegrates with 3.0 • 10 5 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> Bq.


 * 1) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">What is the rate of disintegration after 3 years?
 * 2) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">How long does it take for the rate of disintegration to reach 2.0 • 10 5 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> Bq?


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">5: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">A patient is administered 4.0 • 10 7 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;"> Bq 99m <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tc in connection with a nuclear medicine examination. Calculate the amount of mass of 99m <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tc injected in the patient. The daughter nuclide 99 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Tc is radioactive, but has a very long half-life. Show that the total rate of disintegration in the patient is insignificant one week after the examination.


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">6: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Calculate the rate of disintegration of the following:


 * 1) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">1.0 g natural Lu-metal
 * 2) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">1.0 g natural Sm-metal


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">7: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Recently it was showed that natural Bi is radioactive. How much amount of Bi is required to give a disintegration rate of 10 Bq?


 * <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">8: **

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">In nature 234 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U exist in equilibrium with 238 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U as a daughter product.

<span style="font-family: 'Times New Roman','serif'; font-size: 16px;">include component="backlinks" page="Exercises with Amount of Radioactive Material (number of nuclei, number of moles, weight) and the Law of Radioactive Decay" limit="10"
 * 1) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">How much 238 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U has an equivalent disintegration rate as 1 g 234 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U?
 * 2) <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">Given the amounts from a) is separated as pure 238 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U and 234 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U, how many percent has the amount of 238 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U decreased when the amount of 234 <span style="font-family: 'Times New Roman','serif'; font-size: 16px;">U is halved?