After emission, it quickly picks up two electrons to balance the two protons, and becomes an electrically neutral helium-4 (He4) atom. When an atom emits a beta particle, a neutron inside the nucleus is transformed to a proton.The mass number doesn't change, but the atomic number goes up by 1.The half-life of a radioactive nuclide is defined as the time it takes half of a sample of the element to decay.
A third, very rare type of radioactive decay is called electron absorption.
The rules are the same in all cases; the assumptions are different for each method.
To explain those rules, I'll need to talk about some basic atomic physics. Hydrogen-1's nucleus consists of only a single proton.
Different nuclides of the same element can have substantially different half-lives.) billion years old.
So, if we know how much of the nuclide was originally present, and how much there is now, we can easily calculate how long it would take for the missing amount to decay, and therefore how long its been since that particular sample was formed. We must know the original quantity of the parent nuclide in order to date our sample In order to do so, we need a nuclide thats part of a mineral compound. Because theres a basic law of chemistry that says "Chemical processes like those that form minerals cannot distinguish between different nuclides of the same element." They simply cant do it.