In a large sample of `.^(235)U` (Which is alpha active)

The alpha activity of a 10 kg sample of ._(92)U^(235) that is used in a nuclear reactor is found to be x xx 10^(-8) Bq. If the half of life of uranium - 235 for emitting alpha particles is 7.04xx10^(8) year, then find the value 'x' . (Given 1 year =3.15xx10^(7)s )

The half life of ""_(92)^(238)U against alpha - decay is 13.86xx10^(16) s . The activity of 1 g sample of is

The half life of ._92U^(238) against alpha decay is 1.5xx10^(17)s . What is the activity of the sample of ._92U^(238) having 2.5xx10^(21) atom?

The half life of ._92U^(238) against alpha -decay is 4.5xx10^9 years. What is the activity of 1g sample of ._92U^(238) ?

Almost all of naturally occurring uranium is ._92^238U with a half-life of 4.468xx10^9 yr. Most of the rest of natural uranium is ._92^235 U with a half-life of 7.038xx10^8 yr.Today a sample contains 0.72% ._92^235 U (a)What was this percentage 1.0 billion years ago ? (b)What percentage of the sample would be ._92^235 U in 100 million years ?

._(235)^(239)Pu._(94) is undergoing alpha-decay according to the equation ._(94)^(235)Pu rarr (._(97)^(235)U) +._2^4 He . The energy released in the process is mostly kinetic energy of the alpha -particle. However, a part of the energy is released as gamma rays. What is the speed of the emiited alpha -particle if the gamma rays radiated out have energy of 0.90 MeV ? Given: Mass of ._(94)^(239)Pu =239.05122 u , mass of (._(97)^(235)U)=235.04299 u and mass of ._1^4He =4.002602 u (1u =931 MeV) .