A Planetary Nebula Is A(n)

question 223

Multiple Choice

A planetary nebula is a(n)

• A) contracting spherical cloud of gas surrounding a newly formed star in which planets are forming.
• B) expanding gas shell surrounding a hot, burned-out stellar core.
• C) disk-shaped nebula of dust and gas around a relatively young star, from which planets will eventually form.
• D) nebula caused by the supernova explosion of a massive star.

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Definitions:

(2R,4S)-4-propylhexane-2-thiol

A chiral molecule specified by its configuration, comprising a six-carbon chain with a propyl group and a thiol group at specific positions.

(2S,4R)-4-ethylheptane-2-thiol

A chiral organic compound characterized by a specific three-dimensional configuration, including an ethyl and a thiol group on a heptane backbone.

(2R,4S)-4-ethylheptane-2-thiol

A specific stereoisomer of a compound featuring an ethyl group and a thiol group attached to a heptane chain.

(R)-3-methylpent-1-ene

A specific optical isomer of an organic compound with a branched five-carbon chain, featuring a double bond at the first carbon and a methyl group at the third position.