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2 years ago

lodine-131 is a radioactive isotope with a half-life of 8 days. How many grams of a 50 g sample will be left after 48 days?

Chemistry

1 answer:

RSB [31]2 years ago

4 0

Answer:

0.805 or 0.781 depending on the method used.

Explanation:

Data provided

half life ie t1/2= 8days.

No= 50g

t=48days

Nt=?

Method 1

Formula: Nt= No(1/2)^n

where n= number of half lives.

= t/t1/2 = 48/8

=6.

thus Nt= 50(1/2)^6= 0.781

Method 2

Formula: Nt= Noe^-(lambda)t

where lambda= decay constant

= ln2/ t1/2= ln2/ 8 = 0.086.

thus Nt= 50e^-(0.086×48)= 0.805.

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Answer:

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Explanation:

The excersise can be solved, by the Ideal Gases Law.

P . V = n . R . T

In first step we need to determine the moles of gas:

We convert T° from, C° to K → 20°C + 273 = 293K

We convert P from mmHg to atm → 760 mmHg = 1atm

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We replace: 190 L . 1 atm = n . 0.082 . 293K

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We replace equation at STP conditions (1 atm and 273K)

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Hank's Garage has an air compressor with a holding tank that contains 200L of compressed air at 5200 torr. One day a hose ruptured and all the compressed air was released to a volume of 1370 L at atmospheric pressure.

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Learn more: brainly.com/question/1437490

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