This is the brilliant work of Chris Sims, Senior Writer at Comics Alliance. The original post also gives pointers on how to compose molecules of your favorite superheroes:
Source: "Batman" #228
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Source: We've lost track of where we scanned these, but both are from reprints of early FF issues.
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Source: "Picture Stories from American History," 1945, EC Comics
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Source: "The Tomorrow Syndicate," Book 6 of the series "1963" by Alan Moore, Rick Veitch, and Dave Gibbons, 1993
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"Is there anything else you aren't telling me, Superboy?"
Source: "Superman Annual" #7
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Source: The 1970s Marvel Comic
Source: "Fantastic Four" #21
Source: "Jimmy Olsen" #113