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Cesium- is radioactive and has a half life of years. Calculate the activity of a sample of cesium-. Give your answer in becquerels and in curies. Round your answer to significant digits.

User Hereiam
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1 Answer

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15 votes

The question is incomplete, the complete question is;

Cesium-137 is radioactive and has a half life of 30. years. Calculate the activity of a 6.8 mg sample of cesium-137. Give your answer in becquerels and in curies. Round your answer to 2 significant digits Bq Ci

Answer:

See explanation

Step-by-step explanation:

The formula for activity is;

R= 0.693N/t1/2

N= 6.02 ×10^23 mol × 6.8 ×10^-3g/137 g/mol = 3 × 10^19

Substituting into the formula;

R= 0.693 × 3 × 10^19/30 years

R= 6.93 ×10^17 y^-1

In Bq;

6.93 ×10^17 y^-1 × 1.00y/3.16 ×10^7 seconds

= 2.19 ×10^10 Bq

In Ci;

2.19 ×10^10 Bq/3.7 ×10^10 Bq/Ci

= 0.59 Ci

User Rahim Asgari
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