Unit 5 Review (Physical Science)

Atoms of the same element that have different number of neutrons are called

• radioactive elements

• isotopes

• ionizing radiation

• transmutated ions

Lowest, most stable energy level of an electron is the

• half-life

• excited state

• ground state

• radioactive state

The time it takes for exactly one-half of a radioactive sample to decay is called the

• transmutation

• radioactive state

• ground state

• half-life

Energy level of an electron that is higher and less stable than other levels is the

• excited state

• transmutated state

• ground state

• ionizing radiation

The release of excess energy that allows an unstable nucleus to attain a more stable form is called

• isotopes

• ionizing radiation

• excited state

• transmutation

Changing one element to another or one isotope to another is called

• radiation

• half-life

• transmutation

• decomposition

Decomposition of a nucleus to form a different nucleus is called

• radioactivity

• transmutation

• half-life

• ionizing radiation

The type of radioactive decay that emits a particle that is essentially a helium nucleus and that can be stopped by a sheet of paper is called

• gamma decay

• alpha decay

• beta decay

• transmutation

The type of radioactive decay that involves a fast energetic electron that is emitted from an atomic nucleus and can be stopped by 6 mm of aluminum is called

• gamma decay

• beta decay

• alpha decay

• transmutation

Type of radioactive decay in which the nucleus changes from a higher energy state to a lower level and needs several millimeters of lead to be stopped is called

• gamma decay

• beta decay

• alpha decay

• transmutation