The half-life of a radioactive isotope is three hours. If the initial mass of the isotope were 256 g, the undecayed remaining mass after 18 hours would beA. `16.0g`B. `4.0 g`C. `8.0 g`D. `12. 0 g`

The half-life of a radioactive isotope is three hours. If the initial

1.	The half-life of a radioactive isotope is three hours. If the initial mass of the isotope were 256 g, the undecayed remaining mass after 18 hours would beA. `16.0g`B. `4.0 g`C. `8.0 g`D. `12. 0 g`
Answer» Correct Answer - B `t_(1//2)=3`hours after 18 hours,i.e. after 6 half lines undecayed remaining mass =`(256)/(2^(6))=(256)/(64)=4g`

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The half-life of a radioactive isotope is three hours. If the initial mass of the isotope were 256 g, the undecayed remaining mass after 18 hours would beA. `16.0g`B. `4.0 g`C. `8.0 g`D. `12. 0 g`

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