Scientists Evaluating the Cretaceous Mass Extinction Have Concluded That

question 30

Multiple Choice

Scientists evaluating the Cretaceous mass extinction have concluded that

• A)an asteroid impact was probably the triggering event for the extinction.
• B)only an extraterrestrial impact could have caused such a big extinction event.
• C)climate change would not have been involved in producing the extinctions.
• D)ecological factors such as disease and competition probably caused the dinosaurs to go extinct.

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Definitions:

Reactant Molecules

Substances that take part in a chemical reaction and are consumed to form products.

Transition State

A high-energy state during a chemical reaction where reactants are converted to products, representing a point of maximum energy along the reaction pathway.

Free Energy

A thermodynamic quantity that represents the amount of energy in a system that is available to do work at constant temperature and pressure.

Exergonic Reaction

A chemical reaction that releases energy to the surroundings, often contributing to spontaneous processes, such as cellular respiration.