Unit Five: Nuclear Chemistry

Question 1

C-14 is a radioactive form of a very common element. C-12 is the most abundant and stable form. Based on the graph, where is C-14 relative to C-12 in the band of stability?

Answer 1

C-14 is above C-12 on the band of stability

Question 2

The band of stability is above the line on the graph that has a slope of 1. What does this indicate about the number of protons and neutrons for the majority of elements?

Answer 2

The number of protons and neutrons are equal. This is the case with any nucleus that has up to 20 protons.

As the atomic number increases beyond 20, a different trend becomes apparent. In this range, it appears that a stable nucleus is able to accommodate more neutrons. Stable isotopes have a higher neutron toproton ratio, rising to 1.5/1 for elements having atomic numbers between 20 and 83.

Question 3

What type of decay would stabilize an atom of uranium-238? The atomic number of uranium is 92.

Answer 3

Alpha decay

Question 4

A nuclide has 90 neutrons and 60 protons. Will this nuclide undergo decay? If so, what type?

Answer 4

The nuclide will not decay because it has a 1.5 to 1 ratio of neutrons to protons.

Question 5

A hypothetical isotope has 60 protons and 60 neutrons. What type of radioactive decay would it most likely undergo?

Answer 5

It would undergo alpha decay because ..