Centuries: 16th century - 17th century - 18th century
Decades: 1630s 1640s 1650s 1660s 1670s - 1680s - 1690s 1700s 1710s 1720s 1730s
Years: 1683 1684 1685 1686 1687 - 1688 - 1689 1690 1691 1692 1693
... properties of a substance have sense only when we talk of a *set* of molecules together. For example,I see as plain nonsense asking something like "at wh ...
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