Decades: 520s BC 510s BC 500s BC 490s BC 480s BC - 470s BC - 460s BC 450s BC 440s BC 430s BC 420s BC
Years: 480 BC 479 BC 478 BC 477 BC 476 BC - 475 BC - 474 BC 473 BC 472 BC 471 BC 470 BC
... substances that are insoluble in water can be acids and bases. The most general definition of acids and bases is the Lewis definition. A Lewis acid is an electron ...
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