Chapter 11:Nuclear Chemistry

Artificial transmutation

________ is the change of one atom into another brought about by a nuclear bombardment reaction.

Radioactivity

________ is the spontaneous emission of radiation from a nucleus.

Rutherford

________ was able to show that a beta particle is an electron and that an alpha particle is actually a helium nucleus, He2+.

Gamma

________ rays move at the speed of light and have about 1000 times the penetrating power of a particles.

spontaneous emission

The ________ of a particle from an unstable nucleus is called nuclear decay, or radioactive decay, and the resulting change of one element into another is called transmutation.

regular intervals

At ________, the film is developed and compared with a standard to indicate the radiation exposure.

Radioisotope

________ is a radioactive isotope and radionuclide is the nucleus of a radioactive isotope.

Positron

________ is a positive electron, which has the same mass as an electron but a positive charge.

energy change

The ________ accompanying a nuclear reaction can be up to several million times greater than that accompanying a chemical reaction.

simplest device

The ________ for detecting exposure to radiation is the photographic film badge worn by people who routinely work with radioactive materials.

minimum amount of radioactive material

The ________ needed to sustain a nuclear chain reaction is called critical mass.

Half life

________ is the amount of time required for one- half of a radioactive sample to decay.

Unstable isotopes

________ that have more protons than neutrons are more likely to undergo beta decay to convert a proton to a neutron, whereas ________ having more neutrons than protons are more likely to undergo either positron emission or electron capture to convert a neutron to a proton.

number of flashes

The ________ are counted electronically and converted into an electrical signal.

Nuclear decay

________: Radioactive element → New element + Emitted particle.

Nuclear decay

Radioactive element → New element + Emitted particle

electron capture

process in which the nucleus captures an inner-shell electron from the surrounding electron cloud, thereby converting a proton into a neutron, and energy is released in the form of gamma rays.

critical mass

The minimum amount of radioactive material needed to sustain a nuclear chain reaction