Chemistry
thaywoodgccaz
2016-04-27 16:41:12
He atomic mass of an element is equal to ________. its mass number its atomic number one-twelfth of the mass of a carbon-12 atom the mass of an "average atom" the mass of the heaviest isotope
ANSWERS
CarmineMakanani215
2016-04-27 21:34:47

Its atomic number! The mass number is the number that is much smaller than the atomic number and usually under the formula. 

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