The half-life of Radium-226 is 1590 years. If a sample contains 100 mg, how many mg will remain after 4000 years?

1 Answer

#a_n=17.486" "#milligrams

Explanation:

The half life #=1590" "#years

#t_0=100" "#time#=0#
#t_1=50" "#time#=1590#
#t_2=25" "#time#=2(1590)#
#t_3=12.5" "#time#=3(1590)#

#a_n=a_0*(1/2)^n#

#1 " period"=1590" "# years

#n=4000/1590=2.51572327#

#a_n=100*(1/2)^(2.51572327)#

#a_n=17.486" "#milligrams

God bless...I hope the explanation is useful.