If you start with 1.000 gram sample of the isotope how much time would pass before you have just 0.100 grams of the isotope left

So, you're dealing with a sample of cobalt-60. You know that cobalt-60 has a nuclear half-life of

5.30

years, and are interested in finding how many grams of the sample would remain after

1.00

year and

10.0

years, respectively.

A radioactive isotope's half-life tells you how much time is needed for an initial sample to be halved.

If you start with an initial sample

A

0

, then you can say that you will be left with

A

0

2

→

after one half-life passes;

A

0

2

⋅

1

2

=

A

0

4

→

after two half-lives pass;

A

0

4

⋅

1

2

=

A

0

8

→

after three half-lives pass;

A

0

8

⋅

1

2

=

A

0

16

→

after four half-lives pass;

⋮

Explanation:

now i know the answer