(1) d.
48. The mass of a nucleus is always less than its constituent particles by an
(2) a.
amount called the mass defect The mass of a helium nucleus is 4.000 AMU
(3) e.
but the mass of its two neutrons and two protons is 4.033 AMU. This leaves
a difference of 0.033 AMU. According to the Einstein relation E = mc2, the
loss in mass (m) measured in grams must appear as energy released as a
result of a reaction. The difference of 0.033 AMU between the mass of the
helium nucleus and the mass of its constituent particles, which is the amount
of mass converted into energy to bind the nucleus, is called the mass defect.
Mass defect is the difference between the mass of the_______________
and the mass of its _________________________ particles.
nucleus
49. Select the definition of half life.
a. The time required for all radioactive atoms to disintegrate.
constituent
b. The time required for half of the protons of an atom to depart a
radioactive atom.
c. The time required for half of the number of radioactive atoms to
disintegrate.
d. The time required for all the protons of an atom to depart from a
radioactive atom.
1-35
IT0341
Previous Page
