Are the changes from a to b and from b to c physical or chemical changes?
explain your answer
a = ice
b = water
c = steam

They are physical changes.

Explanation:

This is because there in no chemical reaction taking place, just a physical change.

A physical change in a change in which the chemical structure of the substance does not change. Ice, water and steam are all the same on a molecular level, thus changing from ice to water or from water to steam are physical changes.

A chemical change is a change in which the chemical structure of the substance undergoes a change, since this does not happen going for A to B or B to C they are not chemical changes.

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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