Synopsis
Some 350 million years ago, evolution reached one of its most crucial stages when fish crawled from the water onto the land and became amphibians. Today, newts, salamanders, toads and frogs still survive in great quantities, and there is even one species of frog where the male gives birth from its mouth! Presented by David Attenborough.
Chemical Calculations (J250) | GCSE Bitesize Revision
Spec references J250: C2.1. This video provides an overview of how the masses of subatomic particles are used to calculate atomic masses. It then explains Relative Atomic Mass using chlorine isotopes as an example, followed by an introduction to formula masses, mole calculations, and percentage mass. The video concludes with discussions on the conservation of mass and atom economy. Given its fast pace, the content is likely better suited for revision rather than introducing these concepts.
Reversible Reactions - the Haber process | GCSE Bitesize Revision
This video provides an overview of ammonia production through the Haber process, briefly touching on the necessary conditions but without fully detailing them.