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##### Andy C.

University of Michigan - Ann Arbor

##### Marshall S.

University of Washington

### Video Transcript

for number one were given this isotope of iron and were asked how many electrons that there are, how maney protons are and how many neutrons that are Remember, this is the atomic number, and the atomic number tells it someone. Protons are 26 protons and Adam's electrically neutral. So there's also 26 electrons 26 minus 26 plus. And then remember, this is the mass number, and the mass number is the sum of just the protons and neutrons. Electrons are so tiny they don't even count in the mass number. So I know if protons and neutrons at up to 56 there must be 30 neutrons, I subtracted.

University of Virginia
##### Andy C.

University of Michigan - Ann Arbor

##### Marshall S.

University of Washington