The half-life for the radioactive decay of U−238U−238 is 4.5 billion years and is independent of...

The half-life for the radioactive decay of U−238U−238 is 4.5 billion years and is independent of initial concentration.

Part A

How long will it take for 20% of the U−238 atoms in a sample of U−238 to decay?

Express your answer using two significant figures.

Part B

If a sample of U−238 initially contained 1.1×10¹⁸ atoms when the universe was formed 13.8 billion years ago, how many U−238 atoms will it contain today?

Express your answer using two significant figures.

Solutions

Expert Solution

queen_honey_blossom answered 1 year ago

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