Geology Quiz: Part 15

What is the process by which an unstable atomic nucleus loses energy by radiation?

• Beta decay

• Gamma decay

• Alpha decay

• Radioactive decay

What is an alpha particle composed of?

• 3 protons and 2 neutrons

• 2 protons and 3 neutrons

• 2 protons and 2 neutrons

• 1 proton and 1 neutron

What is the time required for one-half of the original number of parent atoms to be transformed into daughter atoms called?

• Transformation time

• Half-life

• Radiation time

• Decay rate

Which isotope is most useful in measuring the ages of older rocks?

• Uranium-238

• Uranium-235

• Rubidium-87

• Carbon-14

Why do radioactive isotopes make good clocks for dating rocks?

• Their half-lives vary with temperature

• Their half-lives do not vary with chemical reactions

• Their half-lives vary with pressure

• Their half-lives do not vary with environmental factors

What is the time since the isotopic clock was 'reset' called?

• Reset time

• Isotopic age

• Transformation time

• Decay time

What is one of the most precise dating methods for old rocks based on?

• Decay of uranium-238 to lead-206

• Decay of uranium-235 to lead-207

• Decay of carbon-14 to nitrogen-14

• Decay of potassium-40 to argon-40

What can lead isotopes from single crystals of zircon silicate be used to date?

• The oldest rocks on Earth

• The youngest rocks on Earth

• The rocks formed during the last volcanic eruption

• The rocks formed during the last ice age

What is the half-life of uranium-238?

• 0.7 billion years

• 6.0 billion years

• 4.5 billion years

• 2.5 billion years

What is the half-life of uranium-235?

• 4.5 billion years

• 0.7 billion years

• 6.0 billion years

• 2.5 billion years