Answer:
Is about 0.53 angstroms
Explanation:
The "size" of an atom in this definition is related with the nucleus size plus the cloud of electrons that surround the nucleus, in this case, since the Hydrogen in its basic state has only one electron, practically the size of the nucleus is the size of the atom, that is 0.53 angstroms or 5.3 x 10 -11 meters.
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