Question

Which of the following are correct with regard to beta-negative (β-) decay?

a. It involves the ejection of a positron (positive electron)

b. It results in increased atomic number

c. It results in increased atomic mass

d. It results in a daughter nucleus with a high energy state

e. It occurs in a neutron-deficient radio nuclide

Answer 1

a. False. Radio nuclides lose energy and become stable in beta decay by a neutron changing to a proton plus an electron. The electron is ejected from the nucleus with high energy and is referred to as a negative beta particle.

b. True. There is an increase in the number of protons (atomic number).

c. False.

d. True. The daughter nucleus is produced with excess energy and loses this as gamma photons.

e. False. Beta-negative (β-) decay occurs in a radio nuclide with neutron excess.