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The half-life of carbon-14 is 5730 if you start with 10 grams and 11,460 years passed by how many grams of carbon-14 will be remaining???



The half-life of carbon-14 is 5730 if you start with 10 grams and 11,460 years passed-example-1
User Teatro
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2 Answers

7 votes

Answer:

Step-by-step explanation:

User Ubercool
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Answer : The amount of carbon-14 remaining will be, 2.5 grams.

Explanation :

Half-life = 5730 years

First we have to calculate the rate constant, we use the formula :


k=(0.693)/(t_(1/2))


k=\frac{0.693}{5730\text{ years}}


k=1.21* 10^(-4)\text{ years}^(-1)

Now we have to calculate the time passed.

Expression for rate law for first order kinetics is given by:


t=(2.303)/(k)\log(a)/(a-x)

where,

k = rate constant =
1.21* 10^(-4)\text{ years}^(-1)

t = time passed by the sample = 11460 years

a = initial amount of the reactant = 10 g

a - x = amount left after decay process = ?

Now put all the given values in above equation, we get


11460=(2.303)/(1.21* 10^(-4))\log(10)/(a-x)


a-x=2.5g

Therefore, the amount of carbon-14 remaining will be, 2.5 grams.

User Alexander Taylor
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