Al+O2 → Al2O3 Which of the following sets of coefficients would correctly balance the equation and why?

A. 2, 2, 2; because you must use the same coefficient for each substance.

B. 2, 3, 2; because you must have the same number of atoms on each side of the equation.

C. 4, 3, 2; because you must have the same number of compounds on each side of the equation.

D. 4, 3, 2; because you may have the same number of atoms on each side of the equation

D

Explanation:

You balance an equation so that all the elements have the same number of atoms on each side of the equation.

it is the most commonly accepted one

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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