Carbon dating a rock
This assumption is backed by numerous scientific studies and is relatively sound.However, conditions may have been different in the past and could have influenced the rate of decay or formation of radioactive elements.Radiocarbon, or carbon 14, is an isotope of the element carbon that is unstable and weakly radioactive. Carbon 14 is continually being formed in the upper atmosphere by the effect of cosmic ray neutrons on nitrogen 14 atoms.It is rapidly oxidized in air to form carbon dioxide and enters the global carbon cycle.While scientists sometimes conceptualize electrons spinning around an atom's nucleus in a defined shell, they actually fly around the nucleus at various distances; this view of the carbon atom can be seen here in two electron cloud figures (bottom), showing the electrons in a single blob (the so-called s-orbital) and in a two-lobed blob or cloud (the p-orbital). It can link to itself, forming long, resilient chains called polymers.It can also bond with up to four other atoms because of its electron arrangement.
Each helium nucleus has two protons and two neutrons.
While there is no proof that the rates were different in the past than they are today, there is also no proof that they were the same.
Thus radioactive dating relies purely on assumptions.
Under very hot temperatures — greater than 100,000,000 Kelvin (179,999,540.6 F) — the helium nuclei begin to fuse, first as pairs into unstable 4-proton beryllium nuclei, and eventually, as enough beryllium nuclei blink into existence, into a beryllium plus a helium.
The end result: Atoms with six protons and six neutrons — carbon.