Which Event Marks the Beginning of a Supernova

question 111

Multiple Choice

Which event marks the beginning of a supernova?

• A)the onset of helium burning after a helium flash in a star with mass comparable to that of the Sun
• B)the sudden outpouring of X-rays from a newly formed accretion disk
• C)the sudden collapse of an iron core into a compact ball of neutrons
• D)the beginning of neon burning in an extremely massive star
• E)the expansion of a low-mass star into a red giant

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Definitions:

Ethane

A colorless, odorless gas that is the second simplest alkane, consisting of two carbon atoms and six hydrogen atoms (C2H6), used as a fuel and a petrochemical feedstock.

Lewis Structure

A visual chart that demonstrates the atomic linkages in a molecule, including the potential existence of lone electron pairs.

Phosphine

A toxic and flammable gas with the formula PH3, used in the semiconductor industry and as a fumigant.

Structurally

Relating to or pertaining to the arrangement of and relations between parts or elements of a complex entity.