How Do Planetary Scientists Explain the Small Amounts of Hydrogen

question 104

Multiple Choice

How do planetary scientists explain the small amounts of hydrogen and helium in Mercury's atmosphere?

• A) Mercury's large iron core has allowed it to retain these light gases from its primordial atmosphere.
• B) They have escaped from the Sun and drifted to Mercury. Mercury does not retain them, but they are continually replenished from the Sun.
• C) They are outgassed from Mercury's active volcanoes.
• D) The hydrogen at least is formed when the Sun's intense ultraviolet radiation breaks apart the hydrocarbons on Mercury's surface.

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Definitions:

Atomic

Constituting an undivided whole; elementary, with reference to particles or concepts.

Truth-functional Compound

A complex proposition in logic that is made up of simpler propositions and whose truth-value depends solely on the truth-values of these simpler propositions.

Quantifier

In logic, symbols that specify how many objects in the universe of discourse satisfy a given condition.

Atomic Open Sentence

An expression containing a variable that becomes either true or false when a value is substituted for the variable.