The “lead” of a pencil is actually made of a substance called graphite which is made of carbon atoms. The picture shows a close-up of one carbon atom. A hydrogen atom has one proton as the nucleus and ...

The questions in this quiz are suitable for GCSE chemistry students studying atom economy, percentage yield and choosing reaction pathways. If you struggled with the quiz, don't panic - we've got you!

The little number written at the lower right after an atom (subscript) tells how many of that atom are in the molecule. The big number written in front of a molecule (coefficient) shows how many of ...

Electronegativity, an essential characteristic of all elements in the periodic table, measures an atom's ability to attract electrons towards itself within a chemical bond. This vital theoretical ...