After dinner, hector demonstrated to his parents a process that he learned in science class that day. He poured a small amount of sugar into a cup of water and then stirred it until the sugar dissolved. Which process did hector demonstrate? A. How to separate components of a solution

B. How substances dissolve in water to produce pure substance

C. How two pure substances can be combined to form a solution

D. How dissolving a substance in water is an example of chemical reaction

answer:

A pure chemical compound is a chemical substance that is composed of a particular set of molecules or ions that are chemically bonded. Two or more elements combined into one substance through a chemical reaction, such as water, form a chemical compound.

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explanation:

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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