2Mg + O2 → 2Mgo What is the greatest amount of MgO (in moles) that can be made with 7.8 moles of Mg and 4.7
moles of O,? Which is the limiting reactant? Which reactant is in excess, and how many moles
of it are left over?

it would be 4.5 mole left over

Explanation:

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