Asolid is placed in a solution. which observation most likely indicates that a chemical reaction has occurred?
a) the size of the solid has rapidly decreased.
b) the color of the solution has not changed.
c) the solid has bubbles forming on its surface.
d) the temperature of the solution stays the same.

Answer;

C) The solid has bubbles forming on its surface.

Explanation;

-Chemical reactions involves the reaction of reactants that involves rearrangement of their structure resulting to the formation of new substances.

-There are a number of common indicators that are used to show that a chemical reaction has taken place, namely;

- aluminum and copper chloride.

- the chloride ion to separate the aluminum from the oxygen so that the aluminum can react with the copper ions (and the water molecules).

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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