The half-life of a radioisotope is 1.5 hours. If its initial mass is 32g, the mass left undecayed after 6 hours isA. 32 gB. 16 gC. 4 gD. 2g

The half-life of a radioisotope is 1.5 hours. If its initial mass is 3

1.	The half-life of a radioisotope is 1.5 hours. If its initial mass is 32g, the mass left undecayed after 6 hours isA. 32 gB. 16 gC. 4 gD. 2g
Answer» Correct Answer - D `N="mass left" =(N_(0)("initial mass"))/(2^(t)//^(t)_(1//2)` `N=32//2^(4)("since "t//_(t_(1//2))=6//_(1.5)=4)=2g`

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The half-life of a radioisotope is 1.5 hours. If its initial mass is 32g, the mass left undecayed after 6 hours isA. 32 gB. 16 gC. 4 gD. 2g

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