The mass number is the average mass of all isotopes of that element, while the atomic mass is the quantity of protons and neutrons within one atom/isotope. true or false

False

Explanation:

Mass number is the quantity of protons and neutrons within one atom while the atomic mass is the average mass of all isotopes of the element.

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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~ trueboss72

the ratio of the conjugate base to the acid required to attain the desired ph.