Question

How does the atomic number change when it emits an alpha particle?

Answer 1

In the decay of a nucleus, the amendment in binding energy seems because of the mechanical energy of the alpha particle and therefore the daughter nucleus. As a result of this energy should be shared between these two particles, and since the particle and daughter nucleus should have equal and opposite momenta, the emitted particle, and therefore the recoiling nucleus can ever have well-defined energy after the decay. As a result of its smaller mass, most of the mechanical energy goes to the particle.

Complete answer:
Alpha particles contain two protons and two neutrons. Protons are positively charged. Once a nucleus emits an alpha particle, these changes happen:
a) The mass unit decreases by four
b) The number decreases by two
c) The nuclear charge decreases by two
Radon- $219$ decays into polonium- $215$ by emitting an alpha particle. This is the balanced equation for the reaction:
$_{86}^{219}Rn \to _{84}^{215}Po + _2^4\alpha$
The mass number of the nucleus decreases by four, from $219$ to$215$.
The atomic number of the nucleus decreases by two, from $86$ to$84$.
The numbers at the top and bottom give the same totals on both sides.
Polonium nuclei have eighty-four protons, therefore their nuclear charge is$+ 86$. They need two less protons than radon nuclei, which have eighty-six protons and a nuclear charge of$+ 84$.

Note: In studies up to the current point, atoms of one element were unable to vary into totally different components. That is as a result of all the different forms of changes we've talked about solely the electrons were dynamical. In these changes, the nucleus, which contains the protons that dictate that part the associate atom is, is dynamic. All nuclei with eighty-four or additional protons are radioactive and components with less than eighty-four protons each have stable and unstable isotopes. All of those components will undergo nuclear changes and switch into totally different components.