A RaCl2 sample isolated by M. Curie in 1906 contained 91.0 mg of 226 Ra. [226 Ra has a half-life of 1622 years.]
a.) What was the decay rate (in Bq) of this 226Ra sample at the time is was isolated?
b.) Assuming this sample was not diluted of otherwise separated or altered, what would be the decay rate (in Bq) of this same 226Ra sample today [12/2/2010]?