What Atomic Transition Occurs in the Atoms of Hydrogen Gas

question 116

Multiple Choice

What atomic transition occurs in the atoms of hydrogen gas in the spiral arms of the Milky Way Galaxy to produce the 21-cm radio emission?

• A) transition from n = 2 level to n = 1 level in atomic hydrogen
• B) change in rotation of the molecule H₂ about an axis perpendicular to the molecular axis
• C) change in the vibrational state of the H atoms in the H₂ molecule
• D) inversion of the electron spin relative to the proton spin, from parallel to antiparallel

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Definitions:

Vitamin B12

A water-soluble vitamin essential for red blood cell formation, neurological function, and DNA synthesis.

Hydrolysis

A process where a molecule's bond is broken through the use of water.

Amino Acids

Organic compounds that combine to form proteins, serving as the building blocks of life with various functions in metabolism.

Fats

Organic compounds that are made up of glycerol and fatty acids, serving as a major energy source and important for various bodily functions.