Question

a) A sample of Radium-226 contains 145 grams of Radium. If there is now 139 grams of radium left, determine the age of the sample? (Hint - the half-life is stated in the module, from this you can find the decay constant)(3) b) How much Radium will be present in the sample in 66 years from now?

Fig: 1

Fig: 2