Question 1

Once carbon is formed in massive star cores, the majority of nuclei formed from then on willbelong to even numbered elements, due to addition to more helium nuclei as alpha particles.

Accepted Answer

A) True 
 B)False

Question 2

Iron nuclei are the most tightly bound nuclei, which is why their production leads to Type IIsupernovae.

Accepted Answer

A) True 
 B)False

Question 3

Most of the energy of the supernova is carried outward via a flood of:

Accepted Answer

A) gamma rays. 
B) helium nuclei. 
C) protons. 
D) neutrinos. 
E) positrons.

Question 4

If successive generations of stars return material back to the interstellar medium which isenriched in heavier elements, then we expect that old stars are ________ compared to youngerstars.

Accepted Answer

The answer of If successive generations of stars return material...

Question 5

The iron in our bodies came from:

Accepted Answer

A) a planetary nebula, formed at the end of a sunlike star's life. 
B) a Type I supernova, as a result of carbon detonation in a white dwarf. 
C) a Type II supernova that blew the core iron into the interstellar medium. 
D) the initial elements formed during and immediately after the big bang. 
E) the fusion of lighter elements in an alien civilization's nuclear fusion reactor.

Question 6

Contrast the progenitors of a Type I and a Type II supernova.

Accepted Answer

The answer of Contrast the progenitors of a Type I...

Question 7

Can our Sun ever become a nova? Why?

Accepted Answer

The answer of Can our Sun ever become a nova?...

Question 8

For a white dwarf to explode entirely as a Type I supernova, its mass must be:

Accepted Answer

A) at least 0.08 solar masses. 
B) 1.4 solar masses, the Chandrasekhar Limit. 
C) 3 solar masses, the Schwarzschild Limit. 
D) 20 solar masses, the Hubble Limit. 
E) 100 solar masses, the most massive known stars.

Question 9

The heaviest nuclei of all are formed:

Accepted Answer

A) in the horizontal branch. 
B) in dense white dwarfs. 
C) during nova explosions. 
D) in the ejection of matter in the planetary nebula. 
E) in the core collapse that set the stage of Type II supernovae.

Question 10

Novae are more closely related to Type II than to Type I supernovae.

Accepted Answer

A) True 
 B)False

Question 11

Two isotopes of the same element differ only in the number of protons.

Accepted Answer

A) True 
 B)False

Question 12

Which statement about our current knowledge of elements is FALSE?

Accepted Answer

A) We now know of more than 110 elements, both natural and artificial. 
B) 81 stable elements have been found on Earth. 
C) 10 radioactive elements are also found on Earth. 
D) We have now produced over 50 radioactive elements not occurring in nature. 
E) Technetium is found in giant stars, but not yet in nature on the Earth.

Question 13

A star can be a supernova:

Accepted Answer

A) in predictable cycles of decades. 
B) a few times, at unpredictable intervals. 
C) only if it can fuse iron in its core. 
D) before it reaches the main sequence, if it is massive enough. 
E) only once.

Question 14

Looking at the elements that make up our world, which are the products of low versus highmass stars?

Accepted Answer

The answer of Looking at the elements that make up...

Question 15

The iron we commonly find in our surroundings came from:

Accepted Answer

A) the iron core of a massive star which exploded as a Type I supernova. 
B) planetary nebulae. 
C) jets ejected by a rapidly spinning pulsar. 
D) material ejected by a nova explosion. 
E) decay of nickel 56 and cobalt 56 in a supernova remnant.

Question 16

What is stellar nucleosynthesis?

Accepted Answer

A) the formation of heavier elements inside stars 
B) the formation of planetary nebulae by red giants 
C) the formation of stars from a nucleus of contracting material 
D) the formation of white dwarfs, neutron stars, and black holes from stars 
E) the process by which stars form interstellar dust

Question 17

Type I supernovae result from ________ stars which have accreted sufficient additional massvia mass transfer from a close binary companion.

Accepted Answer

The answer of Type I supernovae result from ________ stars...

Question 18

What is the reason a Type I supernova slows its dimming after about 2 months?

Accepted Answer

A) The planetary nebula cooled enough to form a dust shell. 
B) Energy is released from the decay of radioactive cobalt 56 to iron 56. 
C) The supernova remnant suddenly becomes transparent. 
D) The burst of energy carried by neutrinos is finally observed. 
E) Energy from the supernova's shock wave is released as it hits interstellar matter.

Question 19

The maximum mass of a white dwarf is about ________ times the mass of the Sun.

Accepted Answer

The answer of The maximum mass of a white dwarf...

Question 20

What would be most likely to disrupt the normal evolution of a star? Give examples of this.

Accepted Answer

The answer of What would be most likely to disrupt...

Exam 21: Stellar Explosions: Novae, Supernovae, and the Formation of the Elements

Once carbon is formed in massive star cores, the majority of nuclei formed from then on willbelong to even numbered elements, due to addition to more helium nuclei as alpha particles.

Iron nuclei are the most tightly bound nuclei, which is why their production leads to Type IIsupernovae.

Most of the energy of the supernova is carried outward via a flood of:

If successive generations of stars return material back to the interstellar medium which isenriched in heavier elements, then we expect that old stars are ________ compared to youngerstars.

The iron in our bodies came from:

Contrast the progenitors of a Type I and a Type II supernova.

Can our Sun ever become a nova? Why?

For a white dwarf to explode entirely as a Type I supernova, its mass must be:

The heaviest nuclei of all are formed:

Novae are more closely related to Type II than to Type I supernovae.

Two isotopes of the same element differ only in the number of protons.

Which statement about our current knowledge of elements is FALSE?

A star can be a supernova:

Looking at the elements that make up our world, which are the products of low versus highmass stars?

The iron we commonly find in our surroundings came from:

What is stellar nucleosynthesis?

Type I supernovae result from ________ stars which have accreted sufficient additional massvia mass transfer from a close binary companion.

What is the reason a Type I supernova slows its dimming after about 2 months?

The maximum mass of a white dwarf is about ________ times the mass of the Sun.

What would be most likely to disrupt the normal evolution of a star? Give examples of this.