Question 20

three examples of physical change are

a)boiling of water, bursting of a balloon, and crumpling a piece of paper

b)burning of gasoline, rotting of an egg, and exploding fireworks

c)freezing of water, evaporation of gasoline, and rusting a nail

d)sawing of wood, crushing a can, and toasting a marshmallow

Three examples of change in physical structures are A) bursting of a balloon, boiling of water, and crumpling a piece of paper.

Physical changes will be changes influencing the type of a compound substance, however not its synthetic arrangement. Physical changes are utilized to isolate blends into their segment mixes, yet cannot as a rule be utilized to separate mixes into concoction components or less complex mixes.  

Physical changes happen when items or substances experience a change that doesn't change their synthetic synthesis.

As the following activities satisfy the aforesaid criteria they are called physical changes:

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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