You and your team are designing a thermoelectric generator that converts the thermal energy released during the decay of a radioactive material into electrical energy. Such devices are used in deep-space probes such as Voyager 1, which was launched in 1977. Its radioisotope thermoelectric generators are expected to function until the year 2025. The isotope that your team will use is ²³⁸₉₄ Pu (atomic mass = 238.049553 u), which has a half-life of 87.7 years.

(a) If ²³⁸₉₄ Pu undergoes alpha decay, what is the daughter nucleus?

(b) Assuming the daughter nucleus found in (a) has an atomic mass of 234.0409468 u, calculate the energy released in the decay in joules (the atomic weight of an alpha particle is 4.002603 u).

(c) How many atoms are in one gram of ²³⁸₉₄ Pu?

(d) How many atoms in one gram of ²³⁸₉₄ Pu decay after one year?

(e) How much energy is released from one gram of ²³⁸₉₄ Pu during one year?

(f) What is the average power output of one gram during one year (in watts)?