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3 years ago

7

Janice needs to have a gastro-intestinal study. So she is given 375 mg of radiocontrast dye containing Barium-142. The half-life

of Ba-142 is 10.6 minutes and its decay is followed by -ray. After one half -life, of Ba-142 remains . After 31.8 minutes , of Ba-142 remains . After half-lives, 11.7 mg of Ba - 142 remains . After minutes , 0.366 mg of Ba - 142 remains. Finally, after approximately 3.5 hours - half-lives , only 0.000358 mg remains . The dye is no longer visible to the Xray and Janice's study is over .

1 answer:

katovenus [111]3 years ago

5 0

After one half life, 188mg

46.9 mg of Ba-142

After 5 half lives

After 106 minutes

20 half lives , only 0.000358 mg remains

Hope this helps

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The question is incomplete, here is the complete question:

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