What two elements combine to from rust?
Two elements that react to form rust are iron and oxygen.
Rust is generally thought of as a compound of iron and oxygen. So, there are two types of elements in rust. Additionally, because iron is a metal and oxygen is a non-metal, those two elements combine ionically, so it is incorrect to consider a representative particle of rust a molecule. It is accurate to refer to it as a formula unit, or simply a particle.
The two most abundant elements in the Earth's crust are oxygen and silicon. When you combine them, you get silicon dioxide; which depending on the exact form it takes is glass or quartz or sand. They tend to combine further with other elements to produce silicate rocks. The two most abundant elements in Earth as a whole are iron and oxygen. When you combine them, you get iron oxide (rust, hematite, magnetite). The reason iron…