Which is NOT true: - Decay of daughter isotopes of 222Rn that are deposited on dust particles and then inhaled is the most significant health hazard from radon gas. - 222Rn is a monatomic noble gas, and is able to seep out of rocks and soils. - Decay of inhaled 222Rn isotope in the lungs is the most significant health threat from radon gas. - 222Rn is in the radioactive decay series of 238U. - Alpha-particles have limited penetrating power, so alpha emitters are primarily of concern when inhaled or ingested.

A rock contains 0.697 mg of 206pb for every 1.000 mg of 238 U present. Assuming that no lead was originally present, that all the 206pb formed over the years has remained in the rock, and that the t1/2 number of nuclides in intermediate stages of decay between 238U and 206pb is negligible, calculate the age of the rock. (For 238U, 4.5x10⁹ years.) yr =

Bombardment of Uranium-238 with a deuteron (hygrogen-2) generates neptunium-237 and _______________ neutrons. (give answer as whole number)

A rock contains 0.684 mg of 20°Pb for every 1.000 mg of 238U present. Assuming that no lead was originally present, that all the 20°PPB formed over the years has remained in the rock, and that the number of nuclides in intermediate stages of decay between 238U and 200Pb is negligible, calculate the age of the rock. (For 238U, t,2 = 4.5x10° years.) yr

1. The disintegration energy of the decay30 P15 by position emission is 4.30 Mev.  The daughter nuclide, Si has a mass of 29.97396 u. What is the mass of  30P15 ? 2. The nuclide 192Pt78decays to  1880s76 by alpha emission. The mass of  192Pt78 is 191.96146 u  and the mass of  188Os76 is  187.9560  u. Calculate the energy effect accompanying the decay. 3. Calculate the energy released by the fusion process3He + 3He → 4He2 + 2H. The masses of the pertinent atoms are: 3He2 = 3.01603u. 4He2 = 4.00260u. 1H2 = 1007825u.

The following isotopes are all stable : 20Ne, Ne, 22Ne 10+ 10- While the following is not, so what be its decay likely? 23 Ne 10- Alpha Positron Electron capture Beta

You are an archaeologist, and send some leather clothing found at a burial site to be radiocarbon dated. Based on other clues, you think that the leather should be 2500 years old. What activity ought to come back from the lab, in Bq per gram of carbon? (These sorts of checks are important in science.) The base carbon-14 activity is 0.231 Bq per gram of carbon, and the decay constant of carbon-14 is 1.21x104 1/year.

Calculate for the binding energy in MeV per nucleon of 232 Th if the actual mass of the atom is 232.038 amu. Express your answer in 2 decimal places. Do not 90 write the units. Mass of proton = 1.0078 amu; Mass of neutron = 1.0087 amu Speed of light = 3.00 x 108 m/s 1 amu = 1 g/mol = 1.66 x 1027 kg 1 MeV = 1.60 x 10-13

If a hospital purchased 58 mg of radioactive 131I (t1/2 = 8.05 d; beta emission) to treat a patient for thyroid cancer and transport of the iodine took 10.5 days (snail mail) would they still have the necessary 25.0 mg of 131I for the treatment?  [Calculate the actual mass of 131I that would remain when the item arrived at the hospital.]

How many radon-222 nuclei (1/2 = 3.82 d) decay per minute to produce an activity of 7.19 pci? radon-222 nuclei: A bathroom in the basement of a home measures 2.76 m x 3.67 m x 2.77 m. If the activity of radon-222 in the room is 7.19 pCi-L, how many nuclei decay during a shower lasting 5.00 min? decays: dpm