3 ms·
300 Ci is 11 TBq (terabecquerel), or 11·10^12 decays per second. Co-60 has a half life of 166 million seconds, so it was 11·166·10^18/ln 2 atoms=2.6·10^21 atoms
by bonzini 4y ago
300 Ci is 11 TBq (terabecquerel), or 11·10^12 decays per second. Co-60 has a half life of 166 million seconds, so it was 11·166·10^18/ln 2 atoms=2.6·10^21 atoms, which is 0.004 moles (a mole is 6.02·10^23 atoms).
A mole of cobalt 60 weighs 60 g, so it was a quarter of a gram if I did the calculations right.
The ln 2 factor is because the probability of a decay happening in a second is ln 2 divided by the half life.
- moffkalast 4y ago> 166 million seconds Or 5,2 years
- bonzini 4y agoYeah but becquerels are #decays per second, so I need the probability of a decay happening in a second, not in a year. :) Sooner or later the dreaded multiply by 86400*365 will happen.