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 Chapter 25
Nuclear fusion and stars
LEARNING OBJECTIVES
In this chapter you will learn how to:
ârecognize the conditions for nuclear fusion to occur
âcalculate the energy released in fusion reactions
âexplain why energy is released in fusion
âunderstand why the conditions for fusion exist in stellar cores
ârecognize the role of stellar mass in the evolution of the star
âunderstand the protonâproton chain
âuse stellar radii and the HertzsprungâRussell (HR) diagram
âdescribe the evolution of a star off the main sequence
âunderstand the Chandrasekhar and OppenheimerâVolkoff limits, white dwarfs, neutron stars and black holes
GUIDING QUESTIONS
âWhat determines the evolution of a star?
âWhat is the origin of the elements?