Question

After 45 hours, how many grams of the imaginary element 317-Bulldogs will be left if the original sample was 400 grams and the half-life (t1/2) is 9 hour

Answer 1

We know that:

- the original sample was 400 grams

- the half-life (t1/2) is 9 hours

And we must find how many grams of the imaginary element 317-Bulldogs will be left after 45 hours.

To find it, we need to know that

And to determine the amount of a radioactive isotope remaining after a given number half-lives we can use the next formula:

`\text{ amount remaining}=\text{ initial amount}*((1)/(2))^n`

Where n is the number of half-lives.

Now, to use the formula we need calculate n

`n=\frac{\text{ time passed}}{\text{ half life}}=\frac{45\text{ hours}}{9\text{ hours}}=5\text{ hours}`

Then, having that n = 5 we can replace the values in the formula for the amount remaining

`\text{ amount remaining}=400\cdot((1)/(2))^5=12.5g`

ANSWER:

There would be 12.5 grams left of 317-Bulldogs after 45 hours