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Are all atoms the same size i.e. is an uranium atom larger than an oxygen atom?

Atoms from different elements are different sizes. If you are familiar with the periodic table there are trends in size associated with an atoms position in the periodic table. Generally, atomic radius decreases from left to right in a single row of the table. Size increases from top to bottom of the periodic table.

gregory r bradburn

But actually, even though the atoms vary in mass by factors of a couple of hundred, the variation in radius is remarkably small. Most atoms are roughly the same size, in other words, within a factor of 2 or so. Of course, defining "size" for an atom is somewhat ambiguous because atoms have kind of fuzzy edges where the electron clouds gradually fade away.

Arthur Smith

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