Relative dating and radiometric dating are used to determine age of fossils and geologic features, but with different methods. Relative dating uses observation of location within rock layers, while radiometric dating uses data from the decay of radioactive substances within an object.Continue Reading
Relative dating observes the placement of fossils and rock in layers known as strata. Basically, fossils and rock found in lower strata are older than those found in higher strata because lower objects must have been deposited first, while higher objects were deposited last. Relative dating helps determine what came first and what followed, but doesn't help determine actual age.
Radiometric dating, or numeric dating, determines an actual or approximate age of an object by studying the rate of decay of radioactive isotopes, such as uranium, potassium, rubidium and carbon-14 within that object. Radioactive isotopes decay at a fixed rate. This rate provides scientists with an accurate measurement system to determine age. For example, carbon dating is used to determine the age of organic materials. Once something dies, it ceases taking in new carbon-14, and the existing carbon-14 within the organism decays into nitrogen at a fixed rate. Scientists measure the proportion of carbon-14 left in the organism to determine its age.Learn more about Atoms & Molecules
More than any other type of fossil, index fossils define geological time periods for geologists by providing the most useful information about the age of the rock they are found in. Index fossils are also called key fossils or type fossils.Full Answer >
An element in chemistry is described as the simplest form of a substance that cannot be broken down using chemical methods. Elements are composed of atoms with the same number of protons.Full Answer >
Hydrogen peroxide can be manufactured in a number of different ways, but the most common methods involve the reaction of oxygen with isopropyl alcohol and anthraquinone. Some of the uses of hydrogen peroxide include as a bleaching agent and in the manufacture of other chemicals.Full Answer >
The Lewis dot structure for H2SO4, or sulfuric acid, features sulfur at the center surrounded by four oxygen atoms. Two hydrogen atoms attach to two oxygen atoms. The elements are abbreviated by their chemical symbols listed on the periodic table of elements, and electrons shared between them are denoted by small dots. These electrons are called valence electrons.Full Answer >