What makes radioactivity

The effects of radioactivity have been felt on an even grander scale with the meltdown of nuclear power plants throughout history. The heat is used to boil water and create steam, turning a turbine and generating electricity.

Another radioactive process could provide a safe way to generate clean energy: fusion. In contrast to fission, fusion involves joining two atomic nuclei together. Becquerel died 12 years after his initial discovery at age 54, with burns and scars likely from handling radioactive materials, and Marie Curie died several decades later from leukemia. Today our greater understanding of radioactivity allows us to use it much more safely.

Accidents with radioactive materials have decreased in frequency and produce fewer fatalities due to stringent safety measures and thorough emergency responses. Originally published by Cosmos as What is radioactivity? Lauren Fuge is a science journalist at Cosmos. Cosmos is published by The Royal Institution of Australia, a charity dedicated to connecting people with the world of science. Financial contributions, however big or small, help us provide access to trusted science information at a time when the world needs it most.

Please support us by making a donation or purchasing a subscription today. Share Tweet. Radioactivity is a useful but dangerous phenomenon. More on:. These large radioactive elements often undergo alpha decay as it quickly lowers the number of protons and neutrons in the nucleus. There are only 50 naturally occurring nuclides that exhibit radioactivity while there are around stable nuclides. Radioactivity can also be used to describe how much ionizing radiation is released by a radioactive material.

The curie Ci was the original unit for radioactivity and is equal to 3. Another way to measure how radioactive something is is to investigate its half life , since the half life of a nuclide is related to its radiation risk.

One common misconception about radioactivity is that any radioactive object is harmful to human health. This is not the case, however, as small doses of radiation have not been proven to be harmful to humans. In fact, there are many radioactive products that can be purchased and pose no health threats to humans.

Bananas, smoke detectors, some ceramic dishware, cat litter, beer, and brazil nuts are all radioactive. However, in larger doses radiation does have negative effects on health. When radioactive materials decay, they produce ionizing radiation. Simply put, this type of radiation can strip electrons away from atoms or break chemical bonds to make ions.

This causes damage to living tissues that cannot always be repaired. Effects from acute exposure to radiation appear quickly, and include burns and radiation poisoning. The symptoms of radiation poisoning include nausea, weakness, hair loss, and diminished organ function and this radiation sickness can result in death if the dose is high enough.

As well, some radiation is only harmful in certain circumstances. For example, smoke detectors generally contain a source of alpha particles known as americium which is radioactive. The americium is used to detect the smoke. In the smoke detector itself, this source is radioactive but not harmful. However, because of the nature of alpha particles, the Americium is very dangerous if ingested.

Protons and neutrons are about times as heavy as an electron, which orbits the nucleus as a cloud. Electrons are negatively - charged and balance the positive electrical charge of the protons in the nucleus. Yet, we credit the Rutherford-Bohr Theory of Atomic Structure for providing us with a basis for understanding atomic. We can use the periodic table, specifically the atomic number and atomic mass for each element, to determine the structure of neutral atoms.

The atomic number, which is unique for each element, indicates the number of protons in an atom. For example, all hydrogen atoms have 1 proton, all carbon atoms have 6 protons and all oxygen atoms have 8 protons.

Neutral atoms have the same number of protons and electrons. Therefore, hydrogen atoms have 1 proton and 1 electron, carbon atoms have 6 protons and 6 electrons and oxygen atoms have 8 protons and 8 electrons. Atoms are so small that it does not make sense to calculate their mass using the same units we use every day, like ounces or grams.

The atomic mass indicates the number of nucleons protons and neutrons. To calculate the number of neutrons in an atom, we round the atomic mass to the nearest whole number and subtract the atomic number or number of protons from the atomic mass. For example:. Opposite electrical charges of the protons and electrons hold the electrons in orbit around the nucleus of an atom.

Within the nucleus, electromagnetic forces tend to shove the positively charged protons and as a result the entire nucleus apart. However, the nucleus is held together by an attractive, so-called strong nuclear force between nucleons: proton-to-proton, neutron-to-neutron and proton-to-neutron.

The strong nuclear force is helped by the presence of neutrons to help counter the competing or repelling forces of protons or the exchange of a particle, called a meson. The delicate balance of forces among particles keeps the nucleus stable. Any change in the number, the arrangement, or the energy of the nucleons can upset this balance and cause the nucleus to become unstable and create a radioactive atom.

Disruption of electrons close to the nucleus can also cause an atom to emit radiation. As the unstable nucleus attempts to become stable, it emits radiation and changes into a different element as the number of protons changes.

This process is called radioactive decay and it continues until the forces in the nucleus are balanced and stable. Another force, so-called weak nuclear force is responsible for radioactive decay. An example of weak nuclear force is the nuclear fusion reactions that power our sun and provide energy to sustain life on Earth.

Unstable atoms will attempt to become stable by changing into a new isotope or element, and energy is released in the form of ionizing radiation until the forces in the nucleus are balanced and stable. The series of changes that a given radioactive element undergoes is called a decay chain. The following is an example of a decay chain for uranium Source: U. Each radioactive element decays at a unique rate. This rate is known as a half-life; the amount of time it takes for approximately half of the radioactive atoms in a sample to decay into a more stable form.

The image above indicates that radium has a half-life of 1, years. So every 1, years approximately half of the radium atoms in a sample decay and change to radon the next element in the decay chain.