Dating dinosaurs and other old things
Recall that atoms are the basic building blocks of matter.Atoms are made up of much smaller particles called protons, neutrons, and electrons.Protons and neutrons make up the center (nucleus) of the atom, and electrons form shells around the nucleus.The number of protons in the nucleus of an atom determines the element.There are two main applications for radiometric dating.One is for potentially dating fossils (once-living things) using carbon-14 dating, and the other is for dating rocks and the age of the earth using uranium, potassium and other radioactive atoms.(The electrons are so much lighter that they do not contribute significantly to the mass of an atom.) C), also referred to as radiocarbon, is claimed to be a reliable dating method for determining the age of fossils up to 50,000 to 60,000 years.
Carbon-14 is mostly used to date once-living things (organic material). Carbon-14 is constantly being added to the atmosphere.
The illustration below shows the three isotopes of carbon.
Some isotopes of certain elements are unstable; they can spontaneously change into another kind of atom in a process called “radioactive decay.” Since this process presently happens at a known measured rate, scientists attempt to use it like a “clock” to tell how long ago a rock or fossil formed.
Scientists use a technique called radiometric dating to estimate the ages of rocks, fossils, and the earth.
Many people have been led to believe that radiometric dating methods have proved the earth to be billions of years old.