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Scientists study how radioactive isotopes in rocks, such as carbon-14, decay to tell the age of the rock.

Does knowing the half-life of carbon 14 help scientists determine the absolute or relative age of a rock? State your claim. Use evidence to support your claim and explains your reasoning.



Please help before Feb 14 (thats when this is due) thank you!

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Scientists study how radioactive isotopes in rocks, such as carbon-14, decay to tell-example-1

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Whatever is ⬆️ there
User MWB
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Answer:

When the isotopes decay, scientists can find out how old the rock is depending on the radioactive isotope's half-life.

Step-by-step explanation:

Radioactive isotopes are unstable and will decay. For example, when humans die carbon-14 decays. The isotopes will decay into a stable isotope over time. Scientists can tell how old the rock was from looking at the radioactive isotope's half-life, which tells them how long it would take for there to be half the radioactive isotope and half the stable isotope. At the next half-life there will be 25% of the radioactive isotope and 75% of the stable isotope. At the next half life there will be 12.5% radioactive and 87.5% stable.

Example:

Carbon-14 is a radioactive isotope with a half life of 5,730 years. How old would carbon-14 be when there is 75% carbon-14 in the rock?

75% is half of the time before the half-life, so it would be 2,365 years.

Hope this helps. Half life helps scientists find how much the isotope has decayed and the age of the rock.

User Guilherme Franco
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