If only an element's atomic number and weight are provided, the other atomic information that can be determined for a neutral atom is the number of protons, electrons, and neutrons.
Here's why:
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The atomic number indicates the number of protons in the atom, which is also the number of electrons in a neutral atom.
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The atomic weight (or atomic mass) can be used to determine the number of neutrons if you know the atomic number. The number of neutrons can be calculated as follows:
\[ \text{Number of neutrons} = \text{atomic weight (rounded to nearest whole number)} - \text{atomic number} \]
Thus, from the atomic number and atomic weight, you can find the number of protons, electrons, and neutrons for a neutral atom.