UNIT 10: NUCLEAR PHYSICS
Define these terms: atomic mass
fusion
isotope
radioactivity
fission
80. Draw the decay reaction for the beta decay of phosphorus-32. 1532P > -1 0e + 16 32S
81. Draw the alpha decay of Am-240. 95240Am > 24He + 93236Np
82. Which 2 subatomic particles are found in the nucleus of an atom and which one of these holds the
nucleus together? Protons and neutrons are in the nucleus; it’s the neutrons that act as the glue holding the
nucleus together
83. What type of nuclear reaction occurs in the Sun and stars? fusion
84. Determine the number of protons, neutrons and electrons in 212 Po. p = 84, n = 128, e = 84
85. If isotope X had a half life of 15.0 years, how much of isotope X would be left after 105 years had past
if you started with 200 g? 105 / 15 = 7 half lives; 200 divided in half seven times = 1.5625 ( 200 > 100 >
50 > 25 > 12.5 > 6.25 > 3.125 > 1.5625)
86. You have 400 g of isotope Y, and after 30 years you only have 50 g left. What is the half-life of isotope
Y? 400 > 200 > 100 > 50; therefore 3 half lives; if all three half lives are 30 years, then each half life is 10
years