16. Average atomic mass is different from mass number because... O A. the average atomic mass describes the mass number of a single atom, but mass number describes the average of all exact masses among isotopes of an element. B. mass number describes the approximate mass of the nucleus of a single atom, but average atomic mass describes the weighted average of all the exact masses among isotopes of an element. mass number describes the exact mass of a single atom, but average atomic mass describes the average of all mass numbers. O D. mass number describes the approximate mass of the nucleus of a single atom, but average atomic mass describes the largest mass among isotopes of an element.

Calculate the number of neutrons of neutrons 209. Bi. X

Please help me answer questions 3 & 65. 3. Oxidation is A. the loss of protons by an atom or molecule. B. the gain of oxygen by a cell. C. the loss of electrons from an atom or molecule. D. the loss of oxygen from a cell. E. The gain of electrons by an atom or molecule. 65. The atomic number of an atom or element is the number of A. neutrons in the nucleus. B. protons in the orbitals. C. Electrons in the nucleus. D. Neutrons in the orbitals E. Protons in the nucleus.

True or False...and why? a.) If you change number of protons, you have isotopes of an element b.) If you change number of neutrons, ions are created c.) If you change number of electrons, you have a different element

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The relative atomic masses of elements are seldom whole numbers because A. atoms of some elements have different atomic numbers. B. atoms of some elements have different masses. C. atoms of some elements have different numbers of electrons. D. atoms of some elements can form ions.