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MrMuchimi
3 years ago
7

Strontium-90, a radioactive isotope with applications in medicine, has a half-life of approximately 30 years. Out of a 100-gram

sample, approximately how much remains after 170 years? 2 grams 8 grams 17 grams 81 grams
Chemistry
1 answer:
AveGali [126]3 years ago
5 0

There are 2 grams remain

<h3>Further explanation</h3>

Given

t1/2 = 30 years

t = 170 years

No = 100 g

Required

Remaining sample

Solution

General formulas used in decay:  

\large{\boxed{\bold{N_t=N_0(\dfrac{1}{2})^{t/t\frac{1}{2} }}}

Input the value :

\tt Nt=100.\dfrac{1}{2}^{170/30}\\\\Nt=1.969\approx 2~grams

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Answer:

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Explanation:

The <em>coefficients</em> of a <em>chemical equation</em> are the numbers that you put in front of each reactant and product. They are used to balance the equation and comply with the law of mass conservation.

By adjusting the coefficients you obtain the relative amounts (moles) of each product and reactant, i.e. the mole ratios.

Here an example.

The first information is what is called a word equation. E.g. nitrogen and hydrogen react to form ammonia:

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        As you see, it was necessary to modify the coefficients. Now the law of conservation of mass is observed and you get the mole ratios:

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3 years ago
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6 0
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since butane is not found on the periodic table,how could you find the molar mass of butane(mass of one mole of butane molecules
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Hello there!

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