Both the loss of electrons and the removal of hydrogen from the molecule indicate that this is an oxidation reaction, showing that as an antioxidant, vitamin C is itself oxidised.

Commercial heat packs (containing iron and water, or supersaturated sodium acetate) and cold packs (various ammonium salts) can be used to show exo- and endothermicity. Heat packs that contain iron ...

We're looking at combustion and oxidation in relation to chemical reactions. I mean ... I'm going to show you the fire triangle. And this shows the three things that we need for a fire to start.