The iron in steel has a density of 7.86 g/cm3. When iron rusts, it forms hydrated Fe2O3 that has a density of 5.12 g/cm3. What happens to the volume as iron rusts?
Like does it expand? contract? stay the same? expand then contract? <-- that is my question
I want to say that the volume stays the same because density = mass/volume and since the volume won't really change? It would only be the mass that is changing while it rust?
I am confused if that makes any sense. But that is what my logic is for this. So if someone can care to explain what happens to the volume as iron rust it would be great.
As you point out, the question is silly.
The density of rust is less than the density of iron, so for the same mass, rust has more volume.
example: The density of sulfur is 2.07g/cm^3. The density of sulfur dioxide is .0014 g/cm^3. what happened to the volume as sulfur burned? You are correct, the question is silly and ill-conceived.
To determine what happens to the volume as iron rusts, we can compare the densities of iron and rust. The density of a substance is calculated by dividing its mass by its volume.
Given that the density of iron is 7.86 g/cm3 and the density of hydrated Fe2O3 (rust) is 5.12 g/cm3, we can observe the following:
- Since rust has a lower density than iron, it means that the same volume of rust will have a lower mass compared to iron.
- Therefore, as iron rusts and transforms into rust (Fe2O3), it undergoes an increase in volume while its mass decreases.
In summary, when iron rusts, it expands in volume.