Haggenmaker Ch.25 SG

The half-life of a radioactive nuclide is the time it will take for ½ of the original parent nuclides to undergo decay.

Explain the concept of half-life.

atomic mass, sum of the number of protons and neutrons

In the symbol (_Z^A)X, what does the A represent?

chemical symbol

In the symbol (_Z^A)X, what does the X represent?

atomic number, number of protons in nucleus

In the symbol (_Z^A)X, what does the Z represent?

When an atom emits a beta particle, a neutron in the nucleus is converted to a proton. As a result, the atomic number increases by one while the atomic mass remains constant.

What happens to an atom when it emits a beta particle?

Since a gamma ray has no charge and no mass, it does not change the mass or atomic number of an atom. Gamma rays provide a release of energy from a nucleus and are usually emitted in conjunction with other types of radiation.

What happens to an atom when it emits a gamma ray?

When an atom emits a positron, it converts a proton to a neutron, which converts it into an atom of the next lighter element.

What happens to an atom when it emits a positron?

Alpha radiation occurs when the nucleus emits a particle that contains 2 protons and 2 neutrons. Alpha particles are symbolized by (_2^4)He.

What is alpha radiation? What is the symbol for an alpha particle?

Beta radiation occurs when the nucleus emits an electron. The beta particle is symbolized as (_-1^0)e.

What is beta radiation? What is the symbol for a beta particle?

Gamma radiation is a type of electromagnetic radiation that is essentially a high energy photon.

What is gamma radiation?

Nuclear fission is the process of splitting a nucleus into smaller elements.

What is nuclear fission?

Nuclear fusion is the process of two lighter elements coming together to form a heavier element along with the release of a large amount of energy.

What is nuclear fusion?

Positron emission occurs during the conversion of a proton in the nucleus to a neutron. The positron particle emitted has the same mass as an electron, but it has a positive charge. The positron is symbolized by (_+1^0)e.

What is positron emission? What is the symbol for a positron?

Spontaneous emission of rays or particles from certain elements.

What is radioactivity?

Low: Alpha Great: Gamma

Which type of radiation has the lowest penetrating power? Which has the greatest?