Problema Solution
CObalt an element used to make alloys has several isotopes. One of these , cobalt 60, is radioactive and has a half-life of 5.7 years. Cobalt 60 is used to trace the path of nonradiaoctive substances in a system. What is the value of k for cobalt 60???
Answer provided by our tutors
A=(Ao)e^(-kt) (where Ao is the amount of the substance you start with)
A = Ao/2 amount of substance after t = 5.7 years
t = 5.7 the half-life of cobalt 60
k = ?
A0/2 = (Ao)e^(-k*5.7) divide both sides by Ao
e^(-k*5.7) = 1/2
(-k*5.7) = ln (1/2)
k = (-1/5.7)ln (1/2)
k = 0.121604768
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