Pick the radioactive isotope in each set

23/11 na
or
20/9 f

explain why

a)its atomic number is greater than 83
b)it has fewer n than p in the nucleus
c)it is an odd-odd nuclide
none of the above

Fluorine 20 is radioactive and Na 23 is not

None of the reasons listed apply. F-20 just has more neutrons than the nucleus "needs"

To determine the radioactive isotope in each set, we need to analyze the given criteria.

a) "Its atomic number is greater than 83": We can find the atomic number by looking at the denominator of each set. The atomic number represents the number of protons in the nucleus. In the first set, 23/11 Na, the atomic number is 11, which is less than 83. In the second set, 20/9 F, the atomic number is 9, also less than 83. Therefore, none of the isotopes fulfill this criterion.

b) "It has fewer n than p in the nucleus": To determine this, we need to compare the number of neutrons (n) to the number of protons (p) in each isotope. In the first set, Na, the atomic number is 11, indicating 11 protons. As for the number of neutrons, we need to subtract the atomic number from the mass number (the numerator). In this case, 23 - 11 = 12. Therefore, Na has more neutrons than protons. In the second set, F, the atomic number is 9, and the mass number is 20, so the number of neutrons is 20 - 9 = 11. In this case, F has fewer neutrons than protons.

c) "It is an odd-odd nuclide": An odd-odd nuclide is an isotope with both an odd number of protons and an odd number of neutrons. In the first set, Na, the atomic number is 11 (odd), and the number of neutrons is 12 (even), so it does not meet this criterion. In the second set, F, the atomic number is 9 (odd), and the number of neutrons is 11 (odd), making it an odd-odd nuclide.

Based on the criteria given, the only isotope that fulfills one of the criteria is 20/9 F, which has fewer neutrons than protons in its nucleus.