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Svetllana [295]
3 years ago
5

Strontium-90 has a half-life of 29 years. In how many years will a 1 kg sample of strontium-90 decay and reduce to 0.25 kg of st

rontium-90?
Biology
2 answers:
m_a_m_a [10]3 years ago
7 0

Answer:

The weight of Strontium-90 will reduce to 0.25 Kg in 58 years.

Explanation:

Given -

Radioactive isotope sample of Strontium-90 = 1Kg

Half life of Strontium-90 = 29 years

After first half life (i.e 29 years), the weight of Strontium-90

= \frac{1}{2}\\= 0.5 Kg

After second half life (i.e 58 years), the weight of Strontium-90

= \frac{0.5}{2}\\= 0.25 Kg

Thus, the weight of Strontium-90 will reduce to 0.25 Kg in 58 years.

olasank [31]3 years ago
6 0
58 years.
1kg - 0 years
0.5kg - 29 years
0.25kg - 58 years
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