Respuesta :
Answer: Color change and the formation of a solid are the indicators of rusting.
Explanation: Rust is a red colored compound known as iron oxide ( [tex]Fe_2O_3[/tex] ) which is formed when iron comes in contact with oxygen. Equation for rusting follows:
[tex]4Fe(s)+3O_2(g)\rightarrow 2Fe_2O_3(s)[/tex]
Iron metal is grey in color and the oxide formed is red in color.
As seen from the above equation, a solid compound is formed, so we can say that the indicators of rusting are : Color change and formation of a solid.