Here's why:
* Magnesium is highly reactive with oxygen. When it burns, it reacts rapidly and produces a very bright white light and intense heat.
* Iron also reacts with oxygen (that's why it rusts), but the reaction is much slower and less intense. It doesn't produce the same bright flame or heat as magnesium.
It's important to note that burning magnesium is dangerous. It can produce very high temperatures and create a lot of smoke. It should only be handled by experienced individuals with proper safety equipment.
