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The atomic number of iron is 26 and the atomic mass is 55.847. What do these numbers mean in regard to protons, electrons, and neutrons?
o A. There are 26 each of protons and neutrons, and the rest of the mass is electrons.
o B. There are 26 protons and 26 electrons. Some atoms of iron have 29 neutrons; the .847 shows that there is more than one isotope of iron.
o C. There are 26 protons and 29 neutrons. Each particle has an atomic mass of 1.
o D. There are 26 protons and 26 neutrons. Since neutrons have slightly more mass than protons, the mass is greater than 52.
What is "There are 26 protons and 26 electrons. Some atoms of iron have 29 neutrons; the .847 shows that there is more than one isotope of iron."