118 Elements and Their Symbols and Atomic Numbers: The periodic table is a well-organized chart that contains all the known elements in the universe. These elements are building blocks of matter ...

You may use table navigation commands for the screen reader of your choice. The Periodic Table of Elements. Each entry contains the atomic number, chemical symbol, and atomic mass to two decimal ...

The proton number (Z) of an atom is the number of protons it contains. All the atoms of a particular element have the same proton number (number of protons). The atoms of different elements have ...

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

Chemists use symbols and formulae to represent elements and compounds. Word equations and balanced chemical equations represent the changes that happen in chemical reactions. Mixtures - AQA There ...