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lesya [120]
3 years ago
9

A patient is administered 20 mg of iodine-131. How much of this isotope will remain in the body after 40 days if the half-life f

or iodine-131 is 8 days?
Physics
1 answer:
igor_vitrenko [27]3 years ago
4 0

The formula for half-life is:

A_{final}=A_{initial}(\frac{1}{2})^{\frac{t}{h}}

Where A is the amount of iodine-131 initially and after 40 days, t is time, h is half-life of the isotope.  Let's plug in our values to the equation:

A_{final}=20(\frac{1}{2})^{\frac{40}{8}=0.625g

Therefore, the patient has 0.625 grams of iodine-131 after 40 days.

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Answer:

m = 9.6 g

Explanation:

Thermal energy given to helium gas at constant volume is given as

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so here we have

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n = moles

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now we know that

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m = \frac{0.75 \times 32}{2.5}

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4.1 m

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