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3 years ago

The half-life of Co-59 is 35 days. How much of a 610.0-gram sample will remain after 140 days?

Chemistry

1 answer:

vitfil [10]3 years ago

3 0

Answer:

Amount left after 140 days is 38.125 g.

Explanation:

Given data:

Half life of Co-59 = 35 days

Total mass of sample = 610.0 g

Sample remain after 140 days = ?

Solution:

Number of half lives passes during 140 days:

Number of half lives = T elapsed / Half lives

Number of half lives = 140 days / 35 days

Number of half lives = 4

Amount left:

At time zero = 610 g

At first half life = 610 g/2 = 305 g

At second half life = 305 g/2 = 152.5 g

At 3rd half life = 152.5 g/2 = 76.25 g

At 4th half life = 76.25 g /2 =38.125 g

Amount left after 140 days is 38.125 g.

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Answer:

The Kc is 1.36 (but this is not an option, may be the options are wrong, or may be I was .. Thanks!)

Explanation:

Let's think all the situation.

2 ICl(g) ⇄ I₂(g) + Cl₂(g)

Initially 0.20 - -

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React x x/2 x/2

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