Plutonium decays with a half-life of 24,000 years.If plutonium is stored for 72,000 yuears,what fraction of it remains ?

After five half life periods for a first order reaction what fraction of reactant remains ?

A radioactive element has half life period 800 years. After 6400 years what amount will remain?

There is a stream of neutrons with a kenetic energy of 0.0327 eV.If the half life of neutrons is 700 s,what fraction of neutrons will decays before they trael a distance of 10 m?

4 g of radioactive material of half-life 10 years is kept in a store for 15 years.How much material is disintergrated?

The half life of _6C^(14) is 5,700 years .what does it mean?

During nuclear explosion, one of the products is overset 90"Sr with half-life of 28.1 years. If 1mug of overset90"Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically.

A radioactive isotope X with half-life of 693xx10^(9) years decay to Y which is stable. A sample of rock from of the moon was found to contain both the elements X Y in the mole ratio 1:7 . What is the age of the rock ? a) 2.079xx10^(12) years b) 1.94xx10^(10) years c) 1.33xx10^(9) years d) 10^(10) years

The half-life of "_38^90Sr is 28 years. What is the disintegration rate of 15 mg of this isotope.