Students learn to describe the pattern in atomic number, atomic mass and atomic radius. Trends on the Periodic Table: Students learn to describe the pattern in atomic number, atomic mass, 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 are ...

The covalent radius (a measure of how large individual atoms are) shows different trends if you are moving across a period or down a group. A comparison of the relative covalent radii of atoms is ...

Since the invention of the periodic table 150 years ago this month, scientists have worked to fill in the rows of elements and make sense of their properties. But researchers have also pursued a ...

As of 2019, the Periodic Table of the Elements has been around for 150 years. Maybe you've felt a certain chemistry with 2019 but don't know why? Maybe it's because this year marks the 150th ...

The news broke that a railroad car, loaded with pure sodium, had just derailed and was spilling its contents. A television reporter called me for an explanation of why firefighters were not allowed to ...