Tritium is a radioactive isotope of hydrogen that decays by about 5% every year. A large bottle of water that contained 450,000 tritium atoms remained undisturbed for 11 years. How much tritium does the bottle contain now?
To calculate the amount of tritium remaining after 11 years, we can use the formula:
N = N0 * (1 - r)^t
Where:
N = final amount of tritium after t years
N0 = initial amount of tritium
r = decay rate per year (5% = 0.05)
t = number of years
Plugging in the values:
N = 450,000 * (1 - 0.05)^11
N = 450,000 * (0.95)^11
N = 450,000 * 0.3138
N = 141,210
Therefore, after 11 years, the bottle contains approximately 141,210 tritium atoms.