# Question: The half life of a radioactive isotope is known to be

The half-life of a radioactive isotope is known to be exactly 1 h.

(a) What fraction of a sample would be left after exactly 3 h: (1) one-third, (2) one-eighth, or (3) one-ninth?

(b) What fraction of a sample would be left after exactly 1 day?

(a) What fraction of a sample would be left after exactly 3 h: (1) one-third, (2) one-eighth, or (3) one-ninth?

(b) What fraction of a sample would be left after exactly 1 day?

## Answer to relevant Questions

A alpha source gives off alpha particles each with a kinetic energy of 2.78 MeV. At what rate (in watts) is kinetic energy being produced? Prove that the number N of radioactive nuclei remaining in a sample after an integer number (n) of half-lives has elapsed is N –No/2n = (1/2)n No. Here No stands for the initial number of nuclei. An ancient artifact is found to contain 250 g of carbon and has an activity of 475 decays/min. (a) What is the approximate age of the artifact, to the nearest thousand years? (b) What would its initial activity have been? (a) The mass of the nuclide 168O is 15.994 915 u. What is the total binding energy for this nucleus? (b) Determine its average binding energy per nucleon. In a diagnostic procedure, a patient in a hospital ingests 80 mCi of gold-198 (t1/2 = 2.7 days). What is the activity at the end of one month, assuming none of the gold is eliminated from the body by biological functions?Post your question