Review for Nuclear Reactions Test

Which reaction has a greater mass defect, and therefore releases MORE energy?

• fission

• fusion

• alpha decay

• beta decay

• gamma emission

Fusion occurs in what types of stars? May be more than one correct answer.

• Stars with mass of our sun or smaller

• Stars with mass of 1 to 8 solar masses

• Stars more massive than 8 suns

Mass defect occurs because the sum of the masses of individual nucleons is _________________ the mass of the nucleus formed when the nucleons combine into an isotope.

• greater than

• smaller than

Fusion reactions release neutrinos

• true

• false

When positrons collide with electrons, _______________ are released

• alpha particles

• beta particles

• neutrons

• gamma rays

Isotopes with 20 or less protons generally prefer to have a n:p ratio of

• 1.5:1

• 1:1

• 1:1.5

• 0.5:1

• 1:0.5

Isotopes with 83 or more protons are generally _______________ and undergo ____________________.

• stable, beta decay

• stable, alpha decay

• radioactive, beta decay

• radioactive, alpha decay

The process of two light nuclei combining to form a heavier nucleus, and sometimes give off other particles is called ______________.

• fission

• alpha decay

• positron decay

• gamma decay

• fusion

This nuclear reaction results in a daughter nucleus with 2 fewer protons, 2 fewer neutrons and a mass number decreased by 4.

• alpha decay

• beta decay

• gamma emission

• positron emission

• fission

This is often released when radioisotopes undergo alpha or beta decay.

• helium nuclei

• X-rays

• gamma rays

• electrons