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3 years ago

12

Iodine-131, a radioactive substance that is effective in locating brain tumors, has a half-life of only eight days. a hospital

purchased 22 grams of the substance but had to wait seven days before it could be used. how much of the substance was left after seven days?

1 answer:

Ad libitum [116K]3 years ago

7 0

5 days/8 days = 0.625 half lives

<span>fraction left after 0.625 half lives = (1/2)^0.625 </span>

<span>= 0.6484197773 </span>

<span>Amount left = 20*0.6484197773 gms </span>

<span>= 12.97 gms to dp <<<</span>

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