Galaxies

question 37

Multiple Choice

Galaxies

• A) have a variety of shapes.
• B) are evenly distributed in space.
• C) are moving closer to one another.
• D) rarely contain more than one or two million stars.

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Definitions:

Dimethoxy-1,3-butadiene

An organic compound characterized by a 1,3-butadiene backbone with two methoxy groups attached, often used as a chemical intermediate.

Diels-Alder

A [4+2] cycloaddition reaction between a conjugated diene and a dienophile forming six-membered rings.

Diels-Alder

A chemical reaction between a conjugated diene and a substituted alkene (dienophile) to form a cyclic compound.

Reactivity

The tendency of a chemical substance to undergo a chemical reaction either by itself or with other materials.