Once the activity of americium in a smoke detector falls below 5 percent of its original activity, it's no longer able to effectively detect smoke and trigger the alarm. If the half-life of americium-241 is approximately 432.2 years, how many years will it take before the americium-241 is unable to detect smoke? Question 11 options:

A)

10 years

B)

20 years

C)

1,868 years

D)

2 years

C 1,868 years

Explanation:

I just took the test - I tried doing the math and was close but couldn't get it exact; so I guessed and I was correct :)

it is to be noted that an alpha particle is an helium nucleus. so it contains 2 protons 2 neutrons and has a mass number of 4. when alpha decay particles are ejected from the nucleus it gets transformed into an atom which has atomic number less than 2 and a mass number less than 4.

an equation that could represent alpha decay is radium 226 decay of alpha particle forms radon 222.

→

it is a good conductor

explanation: