What is the hardest mineral listed here? a. quartz b. calcite c. gypsum d. corundum

D. corundum

Explanation:

Corundum is a hard mineral. It is tough and stable in nature. It is the hardest mineral after diamond. It remains unaffected by the treatment of acids and environmental agents. Translucent brown color corundum is commonly found in nature.

? you expect us to answer this? ? this is your schoolwork, i don't think we can with this, i think it would considering being

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.

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