First 20 Elements Of The Periodic Table: The atomic number and symbols are important in chemistry. The atomic number of elements gives us an idea about the atomic structure of elements ...

Phosphorus literally means “light-bearer” or “light-bringing,” as the first compound of the element glowed in the dark. A century before it became the name of element 15 in the late 1600s ...

The periodic table, also called the periodic table of elements, is an organized arrangement of the 118 known chemical elements ... in the outermost shell). The first section of Mendeleev's ...

Medeleev’s achievement is an important milestone in a story that stretches over millennia, beginning in the 9th century when alchemist Jabir ibn Hayyan first isolated the chemical elements arsenic (Ar ...

A chemical element ... But what is an element really? It is a more subtle question that you might realise. To get to grips with it, it helps to first understand that atoms, the basic units of ...

Note: This video is designed to help the teacher better understand the lesson and is NOT intended to be shown to students. It includes observations and conclusions that students are meant to make on ...

It treats first of the general properties of matter ... The treatment of the steam-engine is short, and to some extent old-fashioned; the chemical discussion of it, however, is far more complete ...

Shortly after the Big Bang, when the Cosmos was basically a thick cloud of hydrogen and helium, the first stars and galaxies began to emerge from the agglutination of the existing chemical elements.