Everything we can see and touch, and quite a lot that we can’t as well, is made of tiny particles called atoms. Some substances, like particles of this iron, contain only one kind of atom. Iron is an ...

Students learn to classify matter as elements, compounds, and mixtures. Matter: Classification of Matter: Students learn to classify matter as elements, compounds, and mixtures and to distinguish ...

Heavier main-group elements have fundamentally different electronic properties from their lighter congeners. Until the last two decades of the twentieth century, these differences were often masked by ...

Scientific American is part of Springer Nature, which owns or has commercial relations with thousands of scientific publications (many of them can be found at www ...