Nuclear Worksheet
Chem 1400
1. Complete each of the following nuclear transformations.
(a) U + n à_____ + Rb + 2 n
(b) Th à_____ + α
(c) 6Li + _____ à 3H + α
(d) 56Fe + 2H à______ + α
2. Write a balanced nuclear reaction to represent each of the following decay processes.
(a) Sr-90 decay by beta emission
(b) 251Cf decay by alpha emission
(c) tritium (3H) decay by beta emission
(d) fluorine-18 decay by positron emission
3. Carbon-11 (t½= 20 min) is manufactured in hospital basements for incorporation into drug molecules for
medical diagnostic work. Radiation emitted by decaying carbon-11 is detected in such tests and used to locate
the labeled drug molecule in a patient’s body.
(a) Boron-11 is a non-radioactive isotope. Identify two reasons why boron-11 would not work for this test.
1.
2.
(b) Suppose a medical test requires a minimum of10 nanograms (1 ng = 10-9 g) of 11C to be injected into the
patient. As much as 35 min elapses, from the moment of 11C manufacture in the basement, through the drug
synthesis in a hospital laboratory, to the point of injection into the patient. Will 40 ng of 11C made in the
hospital basement be sufficient to have the minimum amount necessary by the time the labeled drug reaches the
patient? Explain, supporting your answer with numerical reasoning.
235
92
1
0
90
37
1
0
23
2
90
4
2
3
4
2
3
4
2
3
