The film discusses the classification of matter into homogeneous and heterogeneous types, focusing on elements, compounds, and mixtures. It explains the properties of two elements, iron and sulfur, ...

This graphic was updated on April 12, 2019, to make clear that the element phosphorus does not appear in the 20 amino acids in the human body, at least initially. These amino acids can, however, be ...

One hundred fifty years after Russian chemist Dmitri Mendeleev published his system for neatly arranging the elements, the periodic table it gave birth to hangs in every chemistry classroom in the ...