Edited Invalid date
5.1 Natural Radioactivity
Stable nuclei are found in most naturally occurring isotopes of elements.
An atom is converted into an atom of a different element when there is a change in the number of protons in the nucleus.
The elements with atomic numbers of 93 and higher are produced in nuclear laboratories.
The mass number in the upper left corner and the atomic number in the lower left corner are the atomic symbols.
The atomic number is equal to the number of protons in the nucleus.
A radioactive isotope of carbon used for archaeological dating has a mass number of 14 and an atomic number of 6.
The mass number is written after the element's 6 protons name or symbol.
In this e 8 neutrons, some stable, nonradioactive isotopes are compared with some radioactive ones.
An unstable nucleus can be formed by emitting radiation.
A nucleus has two protons and two neutrons.
An alpha particle has a mass number of 4, an atomic number of 2 and a charge of 2.
The Greek letter alpha is the symbol for an alpha particle, except that the charge is not included.
Zeros are used to show that a gamma ray has no mass or charge.
An alpha particle has two protons and two neutrons.
Write the symbol for the type of radiation that has a mass number of zero and a 1+ charge.
When a molecule is hit by radiation, electrons may be knocked away.
The cells that are most sensitive to radiation are those that are undergoing rapid division, which include the bone marrow, skin, reproductive organs, and intestinal lining.
Cells that have been damaged may not be able to produce needed materials.
Red blood cells may not be produced if the bone marrow is damaged by radiation.
Birth defects can be caused by damaged sperm cells, ova, or the cells of a fetus.
The cells of the nerves, muscles, liver, and adult bones are not as sensitive to different depths.
Cancer cells are an example of rapidly dividing cells.
Large amounts of radiation are used to destroy cancer cells.
The normal tissue surrounding cancer cells is less damaged by radiation.
Radiation may cause diseases.
Nuclear medicine technologists, chemists, doctors, and nurses are required to use proper radiation protection.
Alpha particles, which have the largest mass and charge of the radiation particles, travel only a few centimeters in the air before they collide with air molecules.
There is a piece of paper, clothing and skin that protects us against alpha particles.
Lab coats and gloves will protect you.
If alpha particles are given off, they can cause serious internal damage.
Alpha particles travel as much as several meters through the air, while the Beta particles move at a very small mass.
They can penetrate up to 5mm into body tissue through paper.
The surface of the skin can be burned, but the particles do not travel far enough to reach the internal organs.
Lab coats and gloves are needed to protect the skin.
Many materials, including body tissues, are affected by the rays.
Exposure to the rays can be dangerous.
Lead or concrete will stop them.
The shielding used for the injections of radioactive materials is made of lead or plastic.
Medical personnel wearing protective clothing and gloves stand behind a shield, keeping them away from the hands and body, when working with radioactive materials.
In a nuclear pharmacy, shielding materials are made.
The properties of radiation and shielding are required.
If you work in a nuclear medicine facility where radioactive materials are present, try to keep the time you spend in a radioactive area to a minimum.
If you stay in a radioactive area twice as long, you will get twice as much radiation.
The lower Try Practice Problems 5.11 show the intensity of radiation received.
If you double your distance from the radiation source, the intensity of the radiation drops to one-fourth of its previous value.
Define the type of particle or radiation for each of the three.
View flashcards and assignments made for the note
Getting your flashcards
Privacy & Terms