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3 years ago

Thorium-234 has a half life of about 25 days. What percent of the thorium will remain after 125 days

Chemistry

1 answer:

solong [7]3 years ago

4 0

Answer:

3.125% will remain after 125 days

Explanation:

Given data:

Half life of Th-234 = 25 days

Percent of thorium remain after 125 days = ?

Solution:

Number of half lives = T elapsed / half life

Number of half lives = 125 days / 25 days

Number of half lives = 5

At time zero =100%

At 1st half life = 100%/2 = 50%

At second half life = 50%/2 = 25%

At third half life = 25%/ 2 = 12.5%

At 4th half life = 12.5% /2 = 6.25%

At 5th half life = 6.25% /2 = 3.125%

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Read 2 more answers

Calculate ∆G ◦ r for the decomposition of mercury(II) oxide 2 HgO(s) → 2 Hg(ℓ) + O2(g) ∆H◦ f −90.83 − − (kJ · mol−1 ) ∆S ◦ m 70.

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Explanation:

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