CHM 1046 Extra Credit 2

CHM 1046 Extra Credit 2 - 5. A radioactive element has a...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
Read sections 19.2 and 19.4 to answer the following questions: 1. The rate constant for the beta decay of thorium-234 is 2.881 x 10 –2 / day. What is the half-life of this nuclide? 2. Consider a certain type of nucleus that has a rate constant of 2.03 x 10 –2 min –1 . Calculate the time required for the sample to decay to one-fourth of its initial value. 3. The number of a certain radioactive nuclide present in a sample decays from 160. to 20. in 39 minutes. What is the half-life of this radioactive species? 4. The half-life of is 28.1 years. How long will it take a 10.0-g sample of to decompose to 0.77 g?
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 5. A radioactive element has a half-life of 2.2 hours. How many hours will it take for the number of atoms present to decay to one-sixteenth of the initial value? 6. An archaeological sample contains 0.670 g of lead-206 and 2.155 g of uranium-238. Assume that all the lead now present in the rock came from the radioactive decay of the uranium and that no appreciable amounts of other radioactive nuclides are present in the sample. The decay rate constant for the uranium is 1.54 10 10 /year. What is the age of the sample?...
View Full Document

Ask a homework question - tutors are online