Question

A chunk of Mg metal is lit on fire. It creates a super bright white light. Once the fire is out there is just a white power left. How do you explain what happened?

Answer 1

Answer:

A chemical reaction between Mg metal and oxygen that produced magnesium oxide (white powder).

Explanation:

Solid magnesium (Mg metal) can react with $O_{2}$ when it is lit. This produces magnesium oxide which is whitish in color. The balanced equation for the chemical reaction is shown below:

$2Mg_{(s)}+ O_{2(g)}$ ⇒ $2MgO_{(s)}$

In the reaction above, Mg is the solid magnesium and MgO is the magnesium oxide which is a white powder.