All these methods point to Earth being very, very old -- several billions of years old.
Young-Earth creationists -- that is, creationists who believe that Earth is no more than 10,000 years old -- are fond of attacking radiometric dating methods as being full of inaccuracies and riddled with sources of error.
A third, very rare type of radioactive decay is called electron absorption.
Simply stated, radiometric dating is a way of determining the age of a sample of material using the decay rates of radio-active nuclides to provide a 'clock.' It relies on three basic rules, plus a couple of critical assumptions.
The rules are the same in all cases; the assumptions are different for each method.
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.
Thats the essence of radiometric dating: measure the amount thats present, calculate how much is missing, and Obviously, the major question here is "how much of the nuclide was originally present in our sample? If an element has more than one nuclide present, and a mineral forms in a magma melt that includes that element, the elements different nuclides will appear in the mineral in precisely the same ratio that they occurred in the environment where and when the mineral was formed. The third and final axiom is that when an atom undergoes radioactive decay, its internal structure and also its chemical behavior change.
The mass number doesn't change, but the atomic number goes up by 1.
Thus, an atom of carbon-14 (C14), atomic number 6, emits a beta particle and becomes an atom of nitrogen-14 (N14), atomic number 7.
In other words, electron absorption is the exact reverse of beta decay.
The mass number doesnt change, while the atomic number goes down by 1.
To keep it short, a nuclide is usually written using the elements abbreviation.