Science often uses carbon 14 to date 'sedimentary rocks'. Radiocarbon (carbon-14) is a very unstable element that quickly changes into nitrogen. Half the original quantity of carbon-14 will decay back to the stable element nitrogen-14 after only 5,730 years. (This 5,730-year period is called the half-life of radiocarbon) At this decay rate, hardly any carbon-14 atoms will remain after only 57,300 years (or ten half-lives).
So if 'sedimentary rocks' are really millions of years old, as evolutionary scientists claim, no carbon-14 atoms would be left in them. Indeed, if all the atoms making up the entire earth were radiocarbon, then after only 1 million years absolutely no carbon-14 atoms should be left!