Isotopes and Radioactive Decay. Calculate the total radioactivity that results from one isotope in the human body. Must understand the concepts of half-life, decay constant, DPM, decay.

K40 (half-life=1.3x10E9 years) composes approximately 0.012% of the potassium found in nature. By weight, the human body is approximately 0.35% potassium. Calculate the total radioactivity that results from K40 decay in a 75 kg human.

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K40 (half-life=1.3x10E9 years) composes approximately 0.012% of the potassium found in nature. By weight, the human body is approximately 0.35% potassium. Calculate the total radioactivity that results from K40 decay in a 75 kg human.

The equation for radioactivedecay is: N(t) = Noe-kt, where No is the initial number of radioactive atoms, N(t) is the number of radioactive atoms left after a time t, and k is thedecay constant. The half-life of carbon 14 is about 5730 years.
Radioactive carbon dating makes the assumption that living things absorb carbon 14

How long would it take for a radioactiveisotope with a half life of 2 weeks to lose at least 70% of its radioactivity?
Describe two clinical uses of Radioactivity.

A radioactivedecay series that begins with 237/93 Np ends with formation of the stable isotope 209/83 Bi. How many alpha particle emissions and how many beta particle emissions are involved in the sequence of radioactivedecay?

3. The half-life of iodine-131, an isotope used in the treatment of thyroid disorders, is 8.04 d.
(a) If a sample of iodine-131 contains 5.0 1016 nuclei, what is the activity of the sample? Express your answer in curies.
(b) If the half-life of iodine-131 were only one-fifth of its actual value, calculatethe factor by wh

I need some help in determining the half-life:
1. A radioactive source has a half life of 74 days and an activity of 370 MBq. what was the activity 30 days ago?
2. A radioactive source has a half life of 60 days. what is the relative activity after one week?
3. An 11- Ci Ir- 192 source is recieved on August 20. Regulator

See attached file for the formula.
Q1)
If a radioactive parent isotopedecays to produce a stable daughter isotope, what will be the daughter to parent ratio (D/P) after 9 half-lives? You should give your answer as a single number.
Q2)
What is the product of the beta minus decay shown below? Fill in the atomic number, m

Three radioactive sources each have activities of 1.0 micro Curies (Ci) at t=0. Their half lives are 1 sec, 1 hour and 1 day respectively
a.) how many radioactive nuclei are present at each source when t=0
b.)how many nuclei of each source decay between t=0 and t=1sec
c.)how many nuclei of each source decay between t=0

Radioactice substances decay exponentially. The amount of radium present at an time t obeys the law Q(t)= Qoe^-kt, where Qo. is the initial amount present and k is a suitable positive constant. The half-life of a radioactive substance is the time required for a given amount to be reduced by one-half. Now, it is known thatthe ha

Question: The naturally occurring isotopes of potassium are:
39 K (abundance 93.10%)
40 k (abundance 0.0118%)
41 k (abundance 6.88%)
40K is radioactiveanddecays by Beta- decay with a half-life of 1.29 multiplied by 10`9 years.
a) How many protons and neutrons does each of the three isotopes of potassium have?
b)