which statement best describes a mole? it is 12 units of a given substance. it contains 6.02 1023 grams of sodium chloride. it is the mass of 12 carbon atoms. it contains 6.02 1023 particles of a given substance.

The statement which correctly describes the mole is; it contains 6.02 × 10^23 particles of a given substance.

The mole refers to the amount of substance that contains the same number of elementary entities as 12 g of carbon - 12. According to Avogadro's law, the number of elementary entities in a substance is 6.02 × 10^23. These elementary entities could be atoms, ions, molecules etc.

Therefore, the statement which correctly describes the mole is; it contains 6.02 × 10^23 particles of a given substance.

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The correct option is;

It contains 6.02 × 10²³ particles of a given substance

Explanation:

A mole of substance is the standard scientific unit of measurement for the quantity of the substance which is made up of a large number of small particles such as molecules, ions, atoms, electrons or other entities.

The General Conference on Weights and Measures defines the mole as the amount of a substance that contains 6.02214076 × 10²³ units of entities

The number 6.02214076 × 10²³, is also known as Avogadro's number.

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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