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3 years ago

14

Carbon-14 has a half-life of approximately 5700 years. How much of a 1000g sample will be left undecayed and still radioactive a

fter 11,400 years?
A: 1000g
B: 500g
C: 250g
D: 125g

1 answer:

Artist 52 [7]3 years ago

4 0

Answer:

option C is correct (250 g)

Explanation:

Given data:

Half life of carbon-14 = 5700 years

Total amount of sample = 1000 g

Sample left after 11,400 years = ?

Solution:

First of all we will calculate the number of half lives passes during 11,400 years.

Number of half lives = time elapsed/ half life

Number of half lives = 11,400 years/5700 years

Number of half lives = 2

Now we will calculate the amount left.

At time zero = 1000 g

At first half life = 1000 g/2 = 500 g

At second half life = 500 g/2 = 250 g

Thus, option C is correct.

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3 years ago

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