Final answer:
Beta particles are electrons ejected at high speeds from a nucleus during beta decay, turning a neutron into a proton and effectively increasing the atomic number without changing the mass number.
Step-by-step explanation:
Beta particles are high-speed electrons that are ejected from the nucleus during certain types of radioactive decay processes, specifically beta decay. Beta particles have an atomic number of -1, a charge of -1, and negligible mass. During beta decay, the conversion of a neutron into a proton and a beta particle results in the emission of the beta particle from the nucleus. This process does not change the mass number of the atom but increases the atomic number by one unit. The newly formed proton remains in the nucleus, lowering the neutron-to-proton ratio, and thus, moving the nuclide closer to the band of stability.
Contrary to alpha particles, which are equivalent to helium nuclei and have a charge of 2+, beta particles are significantly lighter and can be shielded by thin sheets of metal. An example of a beta decay is Carbon-14, which decays into Nitrogen-14 while emitting a beta particle. This transformative process is crucial in reducing the number of neutrons and establishing a more stable nucleus.