Question

Which statements are true? Check all that apply.

Alpha decay emits the same number of protons and neutrons.

Beta decay always emits protons.

Beta decay always emits electrons.

Gamma rays are particles of fast-moving matter.

Gamma rays are a form of electromagnetic radiation.

Answer 1

True:
- Alpha decay emits the same number of protons and neutrons. (An alpha particle is a helium nucleus: 2 protons and 2 neutrons.)
- Gamma rays are a form of electromagnetic radiation. (Gamma rays are high-energy photons.)

False:
- Beta decay always emits protons. (Beta decay can convert a neutron to a proton inside the nucleus, but it does not emit protons; the emitted particle is an electron or positron depending on the type.)
- Beta decay always emits electrons. (There is β− emission of electrons, but there is also β+ emission of positrons and electron capture, so “always” is false.)
- Gamma rays are particles of fast-moving matter. (Gamma rays are massless photons — electromagnetic radiation, not matter.)