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3 years ago

The half-life of cobalt-60 is 5.3 years. after __________ years, 1/4 of the original amount of cobalt-60 will remain.

Chemistry

2 answers:

aleksandr82 [10.1K]3 years ago

7 0

Answer:

10.6

Explanation:APEX

cestrela7 [59]3 years ago

4 0

The number of years required for 1/4 cobalt-60 to remain after decay is calculated as follows

after one half life 1/2 of the original mass isotope remains

after another half life 1/4 mass of original mass remains

therefore if one half life is 5.3 years then the years required

= 2 x 5.3years = 10.6 years

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3 years ago

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The question is incomplete, the complete question is:

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The expression for the calculation of depression in freezing point is:

$\Delta T_f=i\times K_f\times m$