Base your answers
to questions 81 through 85 on the information below.
Iodine has many isotopes, but
only iodine-127 is stable and is found in nature. One
radioactive iodine isotope, I-108, decays by alpha particle emission.
Iodine-131 is also radioactive and has many important medical
82 Determine the number of neutrons in an atom of I-127. 
83 Explain, in terms of protons and neutrons, why I-127 and I-131 are
different isotopes of iodine. 
|Answer--> same atomic number
(protons) but different numbers of neutrons
84 Complete the equation in your answer booklet for the nuclear decay of
Link to ANSWER
85 Determine the total time required for an 80.0-gram sampleof I-131 to
decay until only 1.25 grams of the sample remains unchanged.