Question

How can the nucleus of an atom change?

Answer 1

The nucleus of an atom can change by alpha emission, beta or positron decay, and electron capture.

Explanation:

Alpha emission

A nucleus can become more stable by emitting an α particle.

Another example:

`""_34^75"Se" → _32^71"Ge" + _2^4"He"`

Beta decay

A nucleus can become more stable by having a neutron change to a proton and emitting an electron (a β particle ) and an antineutrino.

Another example:

`""_55^137"Cs" → _55^137"Ba" + _(-1)^0"e" + _0^0bar(ν)`

Positron decay

A nucleus can become more stable by having a neutron change to a proton and emitting a `β^+` particle (a positron or positive electron) and a neutrino from the nucleus.

Another example:

`""_8^15"O"→ _7^15"N" + ""_1^0"e" + ""_0^0 ν_e`

Electron capture

A nucleus can become more stable by capturing an electron from an inner orbital.

This changes a proton to a neutron and simultaneously emits an electron neutrino.

Another example:

`""_4^7"Be" + ""_-1^0"e" → _3^7"Li" + ν_e`