# chemistry

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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?

• chemistry -

k = 0.693/t1/2
Solve for t1/2 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.

• chemistry -

0.30625

• chemistry -

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

• chemistry -

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 Aina-Scottâ€™s Company)
Please be reminded that your Microsoft Office Account is due to expire on the 22nd August,2016
It has to be renewed so as to prevent the account from being suspended sir

Thanks
Oyinmartins
Support Executive

er 15days

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