Element Symbols: Each element is represented by a unique one- or two-letter symbol, usually derived from its English or Latin name (e.g., H for Hydrogen, Au for Gold from "Aurum"). Atomic Number ...

Atomic Number and Atomic Mass: Get here the easy notes on atomic number and atomic mass for all the first 30 elements. Know how to calculate atomic mass using atomic number.

For elements 93-118, which are lab-created trans-uranium elements (elements beyond uranium, which has an atomic number of 92), there is no "natural" abundance, according to the Los Alamos National ...

Atoms of the same element with different numbers of neutrons are called isotopes of that element. The atomic mass in the periodic table is an average of the atomic mass of the isotopes of an element.