Radioactive Thermoelectric Generators

Radioisotope Thermoelectric Generators

Let's break down these words!

• Radioisotope thermoelectric generator is a rather big word. Let's look at each word individually so that we can better understand this topic.

What are radioisotope thermoelectric generators?

• RTGs are devices that convert the waste heat given off by radioactive decay processes into useable electrical energy and are often installed in space-bound objects that require energy and other remote structures/machines that cannot obtain energy efficiently by any other means.

• They have been used as power sources in satellites, space probes, and lighthouses.

Examples of RTGs

• Satellies

• Probes

• Remote lighthouses

Open Ended

What are radioisotope thermoelectric generators?

Open Ended

What are some examples of RTGs?

Isotopes and RTGs

• Radioisotopes are used as fuel for RTGs.

• Isotopes must have specific characteristics to fuel RTGs.

• Its half-life must be long enough to release energy at a constant rate for a certain amount of time, for spacelight use the fuel must produce a large amount of power, and radiation must be easily absorbed and transformed into thermal radiation.

Half-life

• the amount of time it takes for one-half of a radioactive isotope to decay.

• the half-life is constant

Isotopes used for RTGS

• The most frequently used isotopes for RTGs are Plutonium-238, Strontium-90, and Curium-244.

• Let's talk about these isotopes.

Multiple Choice

Isotopes are atoms of the same element that have the same number of __________ but different number of __________ . Therefore, isotopes of the same element have different masses. 

• protons, neutrons
• protons, electrons
• neutrons, protons
• electrons, protons

Multiple Choice

An element is defined by its number of 

• protons
• electrons
• neutrons
• protons + electrons

Multiple Choice

Found in the nucleus of the atom

• electrons only
• protons only
• neutrons and protons
• neutrons and electrons

Plutonium-238

• The first isotope of plutonium

• Plutonium is synthesized by uranium-238 which contained deuterons (nucleus of the deuterium isotope)

• This process created neptunium-238.

• Let's discover the protons, neutrons, and electrons of plutonium-238

Multiple Choice

How many protons, neutrons, and electrons does plutonium-238 have?

• 30 protons, 35 neutrons, 30 electrons

• 65 protons, 74 neutrons, 58 electrons

• 94 protons, 144 neutrons, 94 electrons

Open Ended

What is the mass of plutonium-238? How do you know that?

Strontium-90

• radioactive isotope of strontium

• produced by a nuclar fission and undergoes beta decay into yttrium-90

Multiple Choice

How many protons, neutrons, and electros does strontium-90 have?

• 38 protons, 52 neutrons, 38 electrons

• 40 protons, 62 neutrons, 40 electrons

• 38 protons, 25 neutrons, 38 electrons

Open Ended

What do strontium-90 and strontium-45 have in common?

Curium-244

Let's talk about curium.

Open Ended

Curium is named after who?

Multiple Choice

How many protons, neutrons, electrons does curium-244 have?

• 90 protons, 176 neutrons, 87 electrons

• 87 protons, 145 neutrons, 87 electrons

• 96 protons, 148 neutrons, 96 electrons