Dmitri Mendeleev made order out of chaos when he introduced his periodic table in 1869. Until then, the 63 known chemical elements were scattered without a coherent system, making it difficult for ...

Indeed, nothing quite like it exists in the other disciplines of science. The story of the periodic system for classifying the elements can be traced back over 200 years. Throughout its long ...

Analyses of 3.5-billion-year-old rocks from Australia indicate that some of the microorganisms living when those rocks formed were able to derive energy from sulfur, the first time such a ...