Astronomy quiz question: nucleosynthesis origin of lithium

Astronomy 210 Quiz 7, fall semester 2012
Cuesta College, San Luis Obispo, CA

Nucleosynthesis in the first few minutes after the start of the big bang produced the:
(A) lithium in hybrid car batteries.
(B) hydrogen in Jupiter's atmosphere.
(C) iron in your blood.
(D) calcium in your bones.
(E) (More than one of the above choices.)
(F) (None of the above choices.)

Correct answer: (A)

Hydrogen is merely the raw ingredient of the universe. Light nuclides such as deuterium, helium and lithium are produced by fusion of hydrogen in the cores of main sequence stars, but deuterium and lithium are typically broken apart by the high pressures and temperatures there, such that stars cannot have produced any of the deuterium and lithium present in the universe today. These light nuclides were also produced by similar conditions in the first few minutes after the start of the big bang, but as the universe expanded and cooled, deuterium and lithium that would have been broken apart were preserved and these "fossil" nuclides remain to this day. Iron and calcium are heavier elements that can only be produced in the last stages of a supergiant, and would be dispersed to the rest of the universe during a subsequent type II supernova.

Section 70158
Exam code: quiz07sEcn
(A) : 14 students
(B) : 7 students
(C) : 5 students
(D) : 0 students
(E) : 8 students
(F) : 0 students

Success level: 45% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.56

Section 70160
Exam code: quiz07n0iC
(A) : 13 students
(B) : 5 students
(C) : 1 student
(D) : 0 students
(E) : 6 students
(F) : 0 students

Success level: 56% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.27