How to find the mass of a compound given the half life and activity?

AI Thread Summary
To find the mass of Na2SO4 with an activity of 10.0 mCi, it's essential to understand the relationship between activity, half-life, and the decay constant (k). The decay constant can be calculated using the half-life formula, k = 0.693/t_half. Once k is determined, the activity can be related to the number of radioactive atoms (N) using the formula Rate = kN. Finally, the number of moles of sulfur-38 can be converted to mass using its atomic mass. Understanding these relationships is crucial for solving the problem effectively.
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Homework Statement


What mass of Na2 SO4 has an activity of 10.0 mCi? Sulfur-38 has an atomic mass of 38.0 and a half life of 2.87h


Homework Equations



Half life= 0.693/ k

Rate= kN

The Attempt at a Solution


I'm not sure where to begin the sulfur-38 part is throwing me off
All I need is some hint as to where to begin
 
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What 10 mCi means?

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