What process takes solid co2 from a solid to a gas?

Explanation:

A process in which a solid changes directly into gaseous state without undergoing liquid state is known as sublimation.

For example, when a solid carbon dioxide changes into gas then this process of state change is known as sublimation.

Whereas if gas is changing into solid state then it means that molecules of the gas comes closer to each other due to decrease in their kinetic energy.

This process of gas changing into solid state is known as deposition.    

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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