Unit Review Guide on Fossils and Radiometric Dating unit 4

These flashcards cover key concepts related to fossils, atomic structure, and radiometric dating, essential for understanding geology and dating methods.

What is the process of arranging fossils in correct order called?

Relative dating

What is produced during the decay of unstable nuclei?

Radioactivity

What do we call the time it takes for half of a radioactive sample to decay?

Half-life

What three particles make up the atomic structure of an atom?

Protons, neutrons, electrons

What do all atoms of the same element have in common?

The same number of protons

What are atoms with the same atomic number but different mass numbers called?

Isotopes

What is the term for the original radioactive isotope in decay?

Parent isotope

What is used to date organic material?

Radiocarbon dating (carbon-14 dating)

Which two isotopes are used in radiocarbon dating?

C-14 and N-14

What isotopes are commonly used to date very old items over 100,000 years?

U-238 and P-40

What three things are needed to calculate the age of a rock?

Half-life of the isotope, amount of parent isotope, amount of daughter isotope

What is the currently accepted age of Earth?

4.54 billion years

Why are meteorites and lunar rocks used to estimate Earth's age?

They formed at the same time as Earth

What type of radiometric dating is useful for dating bones from an Egyptian tomb?

C-14 dating

Can scientists use carbon-14 dating to find the age of a very tall, old redwood tree?

Yes, but only for parts less than 50,000 years old.

What is the atomic number of an atom?

The number of protons in the nucleus of the atom.

What is the mass number of an atom?

The total number of protons and neutrons in the atom.

If the half-life of an unstable isotope is 10,000 years, and only 1/8 of the radioactive nuclei remain, how old is the sample?

30,000 years

What is the term for the stable isotope an unstable isotope decays into?

Daughter isotope

What does the rate of decay of radioactive isotopes allow for?

It allows for radiometric dating.