What Best Explains Why Stream Valleys Become Wider Over Time

question 17

Multiple Choice

What best explains why stream valleys become wider over time?

• A) meandering streams undercut their banks and cause mass wasting.
• B) deposition of sediment creates a valley floor.
• C) tectonic uplift causes valleys to widen naturally.
• D) stream velocity becomes greater over time.
• E) streams get further above base level.

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Definitions:

ΔG°

Standard Gibbs free energy change, a thermodynamic quantity indicating the spontaneity of a reaction at standard conditions; negative values suggest spontaneity.

Exothermic

A chemical reaction or process that releases heat to its surroundings.

Endothermic

Describes a process or reaction that absorbs energy from its surroundings, typically in the form of heat.

Equilibrium Concentration

The concentration of reactants and products in a chemical reaction that remains constant over time at equilibrium.