Is iron lawn furniture rusting outside mechanical or chemical weathering?

Weathering is the process of decomposition and disintegration of rocks and minerals at the Earth's surface. It is caused by physical and chemical processes.

When iron is exposed to oxygen, it undergoes a chemical reaction called oxidation, which results in the formation of iron oxide or rust. This reaction is accelerated by the presence of moisture, temperature changes, and other factors.

Therefore, the chemical weathering of the iron lawn furniture is primarily due to the reaction of iron with oxygen in the presence of water and other atmospheric gases.