Dating Methods (halflife) Flashcards
(24 cards)
What is the definition of half-life in dating methods?
Half-life is the time required for half the quantity of a radioactive isotope to decay.
True or False: Half-life is a constant for each radioactive isotope.
True
Fill in the blank: The half-life of Carbon-14 is approximately ____ years.
5730
What is the main principle behind radiometric dating?
Radiometric dating is based on the decay of radioactive isotopes to determine the age of materials.
Which isotope is commonly used for dating recent organic materials?
Carbon-14
Multiple choice: Which of the following isotopes has a half-life of about 4.5 billion years? A) Uranium-238 B) Potassium-40 C) Rubidium-87
A) Uranium-238
What is the formula used to calculate the age of a sample based on its half-life?
Age = (t_half * log(N0/N)) / log(2)
True or False: The half-life of an isotope can change based on environmental conditions.
False
Which dating method uses the decay of potassium-40?
Potassium-Argon dating
What kind of materials can be dated using Carbon-14?
Organic materials, such as wood, bone, and shell.
Multiple choice: Which method is best for dating rocks older than 100,000 years? A) Carbon-14 B) Uranium-Lead C) Thermoluminescence
B) Uranium-Lead
What is the half-life of Uranium-235?
Approximately 703.8 million years.
Fill in the blank: The process of using radioactive decay to estimate the age of an object is known as ____ dating.
radiometric
True or False: Radiocarbon dating can be used for dating fossils.
False
What is the significance of the parent and daughter isotopes in radiometric dating?
The parent isotope decays into the daughter isotope at a predictable rate, allowing age estimation.
Multiple choice: Which of the following is NOT a radiometric dating method? A) Dendrochronology B) Rubidium-Strontium C) Fission Track
A) Dendrochronology
What is the half-life of Thorium-232?
Approximately 14 billion years.
Fill in the blank: The time it takes for a radioactive isotope to decay to one-fourth of its original amount is ____ half-lives.
two
True or False: The half-life of isotopes can be used to date both inorganic and organic materials.
True
What type of dating method is used for very recent geological events, like volcanic eruptions?
Luminescence dating
Multiple choice: Which isotope is used in dating igneous rocks? A) Carbon-14 B) Potassium-40 C) Carbon-12
B) Potassium-40
What is the primary limitation of Carbon-14 dating?
It is only effective for dating materials up to about 50,000 years old.
Fill in the blank: The process of measuring the amount of a radioactive isotope to determine age is called ____ analysis.
isotope
True or False: All isotopes can be used for dating purposes.
False
