P2.7 Flashcards

What is enriched uranium?

What happens for fission to occur?

By what process is energy released in stars?

How are nuclei contained in a fusion reactor?

What is the major source of background radiation?

Why must radioactive waste be stored securely?

What happened to the temperature of the universe as it expanded?

What is a galaxy?

Why are stars in the main sequence stable?

What is a neutron star?

What is the heaviest element formed by fusion in a main sequence star?

How are the chemical elements distributed through space?

What is a fissionable isotope?

Which two fissionable isotopes are used in nuclear reactors?

When does a chain reaction occur?

What is nuclear fusion?

How can nuclei be made to come close enough to fuse?

How long did it take for the temperature of the universe to fall enough so that uncharged atoms were formed?

Why is a black hole black?

When is a black hole formed?

What will the final stage in the life cycle of the Sun be?

What evidence is there that the Sun and inner planets formed from the remnants of a supernova?

What is the name of the process that produces the chemical elements?

When are elements heavier than irons formed?