chemistry
posted by Monique .
A radioactive sample contains 2.45g of an isotope wiht a half life of 3.8 days. How much of the isotope in grams remains after 11.4 days?
please explain

k = 0.693/t_{1/2}
Solve for t_{1/2} and substitute into the equation below.
ln(No/N) = kt
No = starting grams = 2.45 g
N = ending amount. Solve for this.
k = from above calculation.
t = 11.5 days. 
0.30625

100g of radioactive mass has a half life of 5days.calculate the mass decayed off aafter 15days

100g of radioactive mass has a half life of 5days.calculate the mass decayed off aaftGood day sir, My Name is Oyindamola from Enterprise ware Technologies(Mr Seun AinaScottâ€™s Company)
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