One significant difference between gases and liquids is that . a gas is made up of molecules a gas expands to fill its container a gas may consist of both elements and compounds gases are always mixtures All of the above answers are correct

One significant difference between gases and liquids is that a gas expands to fill its container.

Explanation:

One of the biggest differences between liquids and gases is that liquids have a defined volume and gases do not. A gas has no defined shape or volume, it acquires the shape and volume of the container in which it is located. It is the tendency of gases to increase in volume due to the force of repulsion that works between their 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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