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2 years ago

10

If you have 100 grams of a radioactive isotope with a half life of 10 years how much of the isotope will you have left after 20

years

1 answer:

Cerrena [4.2K]2 years ago

3 0

Hey there!

A half-life means after a certain amount of time, half of that substance will be gone/changed after that time.

There are two half lives in 20 years because 20 ÷ 10 = 2.

So, we divide the 100g sample in half 2 times.

100 ÷ 2 = 50

50 ÷ 2 = 25

There will be 25g of the radioactive sample remaining after two half lives.

Hope this helps!

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Answer : The values of $\Delta H^o,\Delta S^o\text{ and }\Delta G^o$ are $33.89kJ,95.94J/K\text{ and }5.299kJ/mol$ respectively.

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Now put all the given values in this expression, we get:

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where,

$\Delta S^o$ = entropy of reaction = ?

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Now put all the given values in this expression, we get:

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Now we have to calculate the Gibbs free energy of reaction $(\Delta G^o)$ .

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