# Chemistry

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A certain radioactive element has a half life of 1 h. If you start with a 1-g sample of the element at noon, how much is left at 3:00 PM? At 6:00PM? At 10:00 PM?

• Chemistry -

1.0 g/2n = ??
where n is the number of half lives.
1/23 = 1/8 g or 0.125
The others are done the same way.

• Chemistry -

i have no idea

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