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 halflife of carbon14 is 5730 if you start with 10 grams and 11460 years passed by how many grams of carbon14 will be remaining class=](https://us-static.z-dn.net/files/d89/189878bd5f81498fc6b437dcbe841357.jpg)
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 :
[tex]k=\frac{0.693}{t_{1/2}}[/tex]
[tex]k=\frac{0.693}{5730\text{ years}}[/tex]
[tex]k=1.21\times 10^{-4}\text{ years}^{-1}[/tex]
Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:
[tex]t=\frac{2.303}{k}\log\frac{a}{a-x}[/tex]
where,
k = rate constant = [tex]1.21\times 10^{-4}\text{ years}^{-1}[/tex]
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
[tex]11460=\frac{2.303}{1.21\times 10^{-4}}\log\frac{10}{a-x}[/tex]
[tex]a-x=2.5g[/tex]
Therefore, the amount of carbon-14 remaining will be, 2.5 grams.