Answer:
Isotopes:
Isotopes are atoms of the same element that have different numbers of neutrons. Neutrons are subatomic particles that are found in the nucleus of an atom. The number of protons in the nucleus determines the element, while the number of neutrons can vary. Isotopes have the same atomic number (number of protons) but different mass numbers (sum of protons and neutrons). For example, carbon-12 and carbon-14 are isotopes of carbon.
Radioactive isotopes:
Radioactive isotopes, also known as radioisotopes, are isotopes that have an unstable nucleus. This means that they can undergo radioactive decay, where the nucleus releases particles and energy in order to become more stable. As a result, radioactive isotopes can emit radiation. Some examples of radioactive isotopes include carbon-14, uranium-235, and iodine-131.
Parent isotopes:
In the context of radioactive decay, a parent isotope is the original radioactive isotope that undergoes decay. It is the starting point in a decay chain. For example, uranium-238 is a parent isotope in the decay chain that eventually produces lead-206.
Daughter isotopes:
Daughter isotopes, also known as daughter nuclides, are the isotopes that are formed as a result of radioactive decay. They are the isotopes that are produced from the decay of a parent isotope. Using the example of uranium-238, lead-206 is a daughter isotope that is formed through a series of decay steps.
Relative dating:
Relative dating is a method used to determine the age of rocks or fossils by comparing their positions or locations in relation to one another. It relies on the principle of superposition, which states that in undisturbed rock layers, the oldest rocks are at the bottom, while the youngest rocks are at the top. Relative dating also takes into account other principles, such as the principle of cross-cutting relationships and the principle of faunal succession. By analyzing the order and relationships of rock layers or fossils, scientists can determine the relative age of geological events.
Absolute dating:
Absolute dating, also known as radiometric dating, is a method used to determine the actual numerical age of rocks or fossils. It relies on the decay of radioactive isotopes. The rate at which radioactive isotopes decay is known and can be used to calculate the age of a sample. One common method of absolute dating is carbon-14 dating, which is used to determine the age of organic materials. Another method is uranium-lead dating, which is used to determine the age of rocks. By measuring the ratio of parent isotopes to daughter isotopes, scientists can calculate the age of the sample.
To summarize:
- Isotopes are atoms of the same element with different numbers of neutrons.
- Radioactive isotopes are unstable isotopes that undergo radioactive decay.
- Parent isotopes are the original radioactive isotopes that decay.
- Daughter isotopes are the isotopes formed as a result of radioactive decay.
- Relative dating determines the age of rocks or fossils by comparing their positions.
- Absolute dating uses radioactive decay to determine the numerical age of samples.