What kind of changes cause iron to rust ?

ways it rust are

1.you put water on it

2.let it sit out side for about a month or 2

                       or

you put the iron in water still wait a month or 2 then

you got the full or sum rusty parts

Explanation:

ether way you need water, air ,and the main thing... IRON

the enthalpy of formation of water is given as -285.8kj/mol, which states that the enthalpy of formation is negative.

negative enthalpy of formation indicates that the heat is released during the reaction process. the heat is released from reaction to the surroundings the enthalpy is expressed with a negative sign with the energy given out in the reaction process.

the formation of water takes place by giving out heat which is -285.8 kj/mol.