A 7.500-mg sample of chromium-55 is analyzed after 14.0 min. and found to contain 0.469 mg of chromium-55. what is the half-life of chromium-55?

2 answers

ln(No/N) = kt

No = 7.500 mg
N = 0.469 mg
t = 14 min
solve for k.
Substitute k into the following:
k = 0.693/t1/2
tanx 4 the help:)