Reference no: EM132592289

In one common type of household smoke detector, the radioactive isotope americium-241 decays by alpha emission. The alpha particles produce a small electrical current because they are charged. If smoke enters the detector, it blocks the alpha particles, which reduces the current and causes the alarm to go off. The half-life of ²⁴¹Am is 433 y, and its atomic weight is 241 g/mol. Typical decay rates in smoke detectors are 690 Bq

1) Write the decay reaction of ²⁴¹Am and identify the daughter nucleus.

²⁴¹Am→α+²³⁷Np

²⁴¹Am→α+²³⁷Bk

²⁴¹Am→α+²³⁹Pa

²⁴¹Am→α+²³⁹Es

²⁴¹Am→α+²⁴¹Cm

2) By how much does the alpha particle current decrease in 1.0 y due to the decay of the americium? (Express your answer to two significant figures.)

3)By how much does the alpha particle current decrease in 40 y due to the decay of the americium? (Express your answer to two significant figures.)

4)How many grams of 241241Am are there in a typical smoke detector? (Express your answer to two significant figures.)(×10^-9 g )