Answer:
Activation energy is needed so reactants can move together, overcome forces of repulsion, and to begin breaking bonds.
Explanation:
Answer: A thing that died a long time ago, and it's bones were preserved in the ground.
Explanation:
Because yes
Yes it is available. It will continue catalyzing the reactions until it becomes completely consumed. That's how enzymes work. They work and are eventually consumed in the process completely without altering the reaction in any way other than speeding it up.
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Answer:
This question appear incomplete
Explanation:
This question appear incomplete. However, fuel is formed through a natural phenomenon involving the conversion of large amount dead and decayed organisms (usually algae and zooplanktons) to combustible fuel through exposure to relatively high temperature and pressure (over millions of years) in the earth's crust. Thus, since this involves a sort of absorption of heat energy (from the earth's crust), it can be referred to be an endothermic reaction.