Radioactive Decay
What is radioactive decay?
The process in which the nuclei of radioactive energy elements break down, releasing fast-moving particles and energy.
What is half-life?
The time it takes for half of the atoms of a radioactive element to decay.
What is Radioactive Dating?
In radioactive dating, scientists first determine the amount of a radioactive element in a rock. Then they compare that amount with the amount of the stable element into which the radioactive element decays.
What do scientists often use to date rocks?
Potassium-40
What is carbon-14, a radioactive form of?
What is radioactive decay? (KC 1)
During radioactive decay, the atoms of one element break down to form atoms of another element.
What occurs naturally in igneous rocks?
Radioactive elements
Why does potassium-40 form decay?
This form decays to stable argon-40 and has a half life of 1.3 billion years.
What happens after an organism dies?
After an organism dies, the carbon-14 in the organism's body decays, which changes to stable nitrogen-14
How do scientists calculate a rock's age?
By using the rate at which elements decay
How do scientists determine the age of a sample?
To determine the age of a sample, scientists measure the amount of carbon-14 that is left in the organism's remains.
The amount of radioactive element ______, but the amount of the new element _______.
Decreases, increases
Why can't carbon-14 be used to date fossils or rocks older than 50,000 years?
Because its life is only 5730 years.