Which is a factor in determining the average atomic mass of an element?
a. atomic number of the most abundant isotope
b. relative abundance of each isotope
c. sum of atomic masses of all isotopes
d. product of atomic masses of all isotopes
e. arithmetic mean of atomic masses of the isotopes

B. Relative abundance of each isotope

Explanation:

Average atomic mass is the average mass of all the isotopes present depending on the relative abundance of each isotope.

Example:

Mass of isotope 1 = 203.973 amu

relative abundance of isotope 1 = 0.014

Mass of isotope 2 = 205.9745 amu

relative abundance of isotope 2= 0.241

Mass of isotope 3 = 206.9745 amu

relative abundance of isotope 3 = 0.221

Mass of isotope 4 = 207.9766 amu

relative abundance of isotope 4 = 0.574

Formula used for average atomic mass of an 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.

that's it!

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~ trueboss72

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