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horrorfan [7]
3 years ago
10

Americium-241 is used in smoke detectors. It has a first-order rate constant for radioactive decay of k = 1.6x10^−3yr−1. By cont

rast, iodine-125, which is used to test for thyroid functioning, has a rate constant for radioactive decay of k = 0.011 day−1.
(a) What are the half-lives of these two isotopes?
(b) Which one decays at a faster rate?
(c) How much of a 1.00-mg sample of each isotope remains after three half-lives?
(d) How much of a 1.00-mg sample of each isotope remains after 4 days?
Chemistry
1 answer:
Vika [28.1K]3 years ago
4 0

Answer:

A. 433 years and 63 days

B. Iodine

C. 0.125mg

D. 1.00mg

Explanation:

A. Americium

The formula of a radioactive decay constant half life is t = 0.693/k

Where k is the decay constant.

For americium, k = 0.0016

t = 0.693/0.0016 = 433.125 apprx 433 years

For iodine, k = 0.011

Half life = 0.693/0.011 = 63 days.

B. Iodine decays at a faster rate.

C. After three half lives

For both, first half life yields a mass of 0.5mg, next yields 0.25mg, next yield 0.125mg

D. 1.00mg still remains.

Half life is high for both so the decay after one day is insignificant.

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Answer:

Explanation:

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This is an example of oxidation of carbon .

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6CO₂  ( Carbon dioxide ) + 6H₂O ( Water ) --------------> C₆H₁₂O₆( Glucose ) + 6 O₂  ( Oxygen ).

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8 0
2 years ago
Use the equation: 2 kclo3 2 kcl + 3 o2 to write the mole ratio needed to calculate: (a) moles of kcl produced from 3.5 moles of
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Answer:-

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(b) 3

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So 3.5 moles of KClO3 will give 3 moles of KCl.

Again

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