Physical properties are: - those that a substance displays only through changing its composition. - those that cause atoms and molecules to change. - those that a substance displays without changing its composition. - identical for all solid matter. - none of the above

The answer to your question is: the third option

Explanation:

- those that a substance displays only through changing its composition. This option is wrong, in a physical property the matter do not change its composition.

- those that cause atoms and molecules to change. chemical properties also made that atoms and molecules change so this option is wrong.

- those that a substance displays without changing its composition. This is the correct answer, in a physical property matter do not change its composition.

- identical for all solid matter. physical properties are different for every substance, so this option is wrong.

- none of the above. it not correct, there is a correct option.

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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~ trueboss72